The overshadowing political event of April was the ongoing United Front of Democracy Against Dictatorship (UDD) demonstration that eventually escalated into the Songkran riots.

               In early April, UDD demonstrators, commonly referred to a red-shirts, made small forays from their main Government House protest site to demonstrate elsewhere, including the Finance Ministry. Prime Minister Abhisit Vejjajiva spoke frequently to assert that he would not allow a civil war or uprising, though peaceful protest would be tolerated. He signaled that he would not invoke emergency powers to quell a protest, though he also insisted that protesters must act within the limits of the law. Already there were signs that things were getting out of hand; Abhisit’s motorcade was attacked as it departed the site of the upcoming ASEAN summit in Pattaya. Other government and Privy Council sources, including Newin Chidchob and Gen Prem Tinsulanonda, spoke out to denounce Thaksin and the red-shirt movement as aiming to overthrow or damage the monarchy.
               On 8 April, the UDD carried through on its intention to escalate its rally outside Government House, and also surrounded the residence of Privy Council President Gen Prem Tinsulanoda. Reports varied, but observers and security sources say that demonstrators numbered about 100,000. UDD demanded that Prime Minister Abhisit Vejjajiva, and Privy Council members Prem, Gen Surayud Chulanont and Charnchai Likitjitta all resign; in their demands, they stated that national administration must continue under constitutional monarchy. In the evening, Thaksin made another video address to the crowd, calling for them to remain in place for three more days, and for people and officials to resist official orders. He also declared that he was not doing this for himself, as he did not care whether he returned to Thailand, but rather for the sake of the country; he said “let me be the last victim of the brutality of the bureaucratic polity.” Demonstrators were apparently quite peaceful and orderly, though there were reports of news teams being threatened, and one news team was attacked and chased away after reporting that the number of demonstrators was only about 20,000. Authorities continue to speak of being concerned that some “third hand” may provoke violence. UDD demonstrators also continued to rally elsewhere in the country. Some journalists reported that speaking with demonstrators, some assert that they do not support Thaksin but are rallying to preserve democracy.
               On 9 April the demonstration continued, with group of demonstrators (some possibly not under the direction of UDD leaders) blocked roads in major areas including Democracy Monument and Victory Monument. UDD leaders also threatened to disrupt the ASEAN summit in Pattaya on 10 April. Leaders eventually pulled demonstrators back to the main Governemnt House site, but not before Prime Minister Abhisit announced that 10 April would be a public holiday for civil servants (and schools).
                As threatened, the ASEAN summit was disrupted. On 10 April, demonstrators reported simply walked through at least one layer of security (police checkpoints on the road up to the Royal Cliff Beach Hotel in Pattaya), before being temporarily halted by a group of blue-shirted people identifying themselves as Glum Rak Paendin Geut and claiming to be local businesspeople. There were later allegations, however, that at least some were police officers and soldiers brought in from the northeast by Newin Chidchob. Blue-shirts had previously appeared to oppose People’s Alliance for Democracy at Suvarnabhumi airport, and the red-shirt demonstrators outside the residence of Privy Council President Gen Prem. Red and blue groups clashed, leaving about a dozen people injured. Eventually, the red-shirts pushed on to the hotel doors and then into the hotel itself. Demonstrators occupied the hotel for about two hours, and reportedly dispersed very shortly after Prime Minister Abhisit announced that the summit was being postponed. Abhisit declared a state of emergency in Pattaya and branded demonstrators who stormed the ASEAN summit as enemies of the state who would face legal action. UDD leaders declared the disruption of the summit a victory and urged supporters to keep demonstrating in Bangkok until the government would be forced to resign.  
              On the morning of 12 April, UDD leader Arisman Pongruangrong was arrested at his home under Criminal Code Article 116 on charges of inciting insurrection in connection with the storming of the Royal Cliff Beach Hotel in Pattaya. In response, UDD demonstrators blocked the roads outside the Criminal Court on Ratchadaphisek Road and the Royal Thai Police Office on Rama 1 Road to demand Arisman’s release. The government in turn responded by invoking a state of emergency in Bangkok and surrounding provinces. Shortly thereafter, about 1,000 red-shirts surrounded the Interior Ministry, from where Prime Minister Abhisit Vejjajiva made the emergency announcement. Demonstrators then stormed the ministry compound, apparently in an attempt to capture or attack Abhisit and Deputy Prime Minister Suthep Thaugsuban. The prime minister’s car was damaged in the escape, but a vehicle carrying his bodyguard was stopped and smashed; a guard and a police officer were assaulted and taken to the UDD demonstration site at Government House before eventually being released and sent to hospital. Later, the prime minister’s secretary-general, Nibhon Phromphan, was attacked at the Interior Ministry, dragged from his car and beaten. At least one shot was fired during the incident. Elsewhere, red-shirts blocked roads, commandeering several public buses for use as road blocks. Abhisit went on television to appeal for calm and to accuse protesters of trying to incite violence. Thaksin and UDD leaders reportedly egged demonstrators on, with Thaksin promising to return to Thailand if authorities attempt to use force to disperse his supporters. UDD-controlled areas became no-go areas for Thai journalists, as UDD supporters denounced most Thai media coverage as biased against them and took to attacking Thai reporters. UDD reinforced its protest site at Government House, adding barriers of vehicles and people around the main area. UDD claimed that two UDD members were shot to death at the Interior Ministry (but later appeared to drop this claim). Meanwhile, in response to the Arisman’s arrest and the state’s blocking of UDD media outlet DStation, UDD supporters in Chiang Mai, Chiang Rai, Lampang, Phitsanulok, Udon Thani, Lamphun, Ubon Ratchathani, Nakhon Ratchasima, Nong Khai, Mukdahan and Chanthaburi rallied in various numbers, blocking roads and rail lines, and surrounding provincial and city halls.
               In the pre-dawn hours of 13 April, soldiers and police moved against UDD red-shirted demonstrators at several locations around Bangkok, notably Din Daeng  and Victory Monument. Authorities say that 113 people were injured in the course of the actions, in which soldiers and police armed with shields, batons, tear gas, water cannons and assault rifles dispersed rioters—officials say they fired into the air rather than at rioters (this was later changed to the assertion that live rounds were fired into the air while blank rounds were fired with barrels leveled to rioters). Rioters were reportedly armed with petrol bombs, stones and firearms; they set tires and buses alight in the course of resisting authorities. In some areas, residents joined authorities in driving off the UDD rioters; in Nang Loeng area, two residents were reportedly shot dead during the fight, and nine other people were injured. Rioters used public buses as barricades and also rigged buses to run driverless at soldiers. Liquefied petroleum gas tanker trucks were positioned at various locations, including Din Daeng and near Democrat Party headquarters, apparently as a threat of mass destruction. (Deputy government spokesman Supachai Jaisamut accused Gen Chaisit Shinawatra, a cousin of Thaksin Shinawatra, of commandeering the Siam Gas trucks for UDD; Chaisit, chairman of Siam Gas, denied the accusation.) Authorities also took over the Thaicom satellite station in at Lum Kaew, Pathum Thani, depriving UDD of its main media tool, satellite television station DStation. Despite Prime Minister Abhisit’s insistence that no protesters were killed in the course of these actions, UDD figures, claimed that many supporters were shot and apparently killed, and then secreted away by the military (in subsequent days, it appeared to become evident that there were no mass killings). During the violence, a group of Thaksin supporters led by former Senate speaker Suchon Chaleekrua and retired police general Salang Bunnag petitioned the King to intervene to end retaliation against UDD demonstrators; the petition stated that demonstrators are protesting due to dissatisfaction with double standards in the justice system and the government’s exercise of power. 
               At 10am on 14 April, with police and soldiers surrounding the UDD camp outside Government House after having largely dispersed red-shirt groups elsewhere in the city, UDD leader Veera Musikhapong announced the end of the UDD demonstration at Government House and called for demonstrators to board buses provided by authorities and disperse. He said that any further violence in Bangkok would not involve UDD demonstrators. Leader Natthawut Saikua declared that UDD had stopped the protest but not the fight for democracy, and that they would separate for a while before reuniting. Supporters pledged defiance as they boarded buses. Meanwhile, however, red-shirts confronted soldiers at Yommarat intersection. Other holdout groups refused to step down, with about 500 people removing their red shirts and making their way to Sanam Luang. UDD leaders Veera, Natthawut, Weng Tojirakarn and Soporn Attakorn surrendered to police after police issued arrest warrants for them and 10 other UDD leaders including Thaksin and Jakrapob Penkair on charges of inciting lawlessness and causing chaos. Veera, Natthawut and Weng were held without bail, but Soporn was released without being charged. Jakrapob refused to surrender. The Bangkok Mass Transit Authority says that rioters seized 52 buses and torched 20 of them.
               On 15 April, the bodies of two security guards were found, bound, gagged and apparently beaten, in the Chao Phraya river. The two were reportedly last seen alive Monday night, declaring the intention to go join red-shirt demonstrators after an evening of drinking at their company compound. Police reportedly said they suspected the motive for the killing was robbery.    
               In the days following the Songkran riots, police raided DStation in Bangkok as well as various pro-Thaksin community radio stations around the country in what appeared to be part of an effort to dismantle red-shirt media networks. Prime Minister Abhisit defended his government’s order to close certain community radio stations, saying that the stations were attempting to incite riots.
UDD leader Jakrapob Penkair left the country to avoid arrest in connection with the violence over Songkran and to establish an office from which to continue the UDD movement. He complained that the legal standards are clearly unfair and unjust, and there is not justice waiting for him in Thailand. Puea Thai MP and UDD leader Jatuporn Prompan invoked parliamentary immunity to avoid arrest. From abroad, Jakrapob spoke of the possibility of UDD being driven underground, and possibly becoming an insurgent organization. The some media outlets portrayed such statements as threats, though some observers commented that the statements could just as easily be interpreted as warning of what may happen if the authorities suppress channels for dissent. Nevertheless Puea Thai and UDD figures quickly disowned Jakrapob’s remarks.
               Cabinet formed a committee, composed largely of state officials and chaired by PM’s Office permanent secretary Nathi Premrasmi, to gather information about the events of the crackdown and produce an accurate account for the public. The government asserts that two people died and over 130 were injured.
               On 23 April, Criminal Court ruled against a petition challenging the legitimacy of the emergency decree, though reporting on the legal justification for the decision was sketchy.
               On 24 April cabinet ended the state of emergency. Veera, Nathawut, and Weng were released on bail, on condition that they do not engage in any acts of provocation, disrupt police investigation of the recent riots, or leave the country; about 20 other UDD figures had already been released on bail.
               Following the Songkran riots, Thaksin ceased making calls for a people’s revolution and urged his supporters to act peacefully. He said that he would humbly urge the King to intervene and help heal the country’s conflict. He also reportedly said that he would urge supporters to participate if the government attempts to reconcile. Thaksin did, however, assert that the government instigated the violence; he also claimed that the red-shirts had been infiltrated by trouble-makers. The Foreign Ministry revoked Thaksin’s passport on grounds that he had incited action that had damaged the country. Thaksin, however, continued to travel, apparently using passports issued by other countries.
               Political observers and pundits generally concluded that the government emerged from the ordeal strengthened, and the red-shirt movement weakened. Clearly, the military was much more cooperative with the Abhisit government than it was with its People Power predecessors in the face of People’s Alliance for Democracy demonstrations. At the same time, the reputation that the UDD had been building of restrained, peaceful protest was shattered. There were rumors of Puea Thai MPs preparing to abandon the party, which has close ties to the UDD.
               While the Songkran events dominated the month, there were some other significant occurrences.
               In early April, the Office of the Attorney-General’s criminal litigation department deferred a decision on prosecuting nine People’s Alliance for Democracy (PAD) leaders on charges of illegal assembly, threatening or using force to provoke unrest, and defying orders of state officials until 28 May; prosecutors said that they need to question more witnesses. Following the quick arrest of UDD leaders after the Songran violence, UDD complained that authorities and the government were exercising a double standard by letting enthusiastically pursuing UDD while letting proceedings against PAD languish.
               The Election Commission absolved the Democrat Party of two separate complaints filed by Senator Ruangkrai Leekitwattana and Puea Thai MP Surapong Towijakchaikul. In one ruling, the EC decided that the democrats had not committed an election offence by declining to field candidates in some provinces during the January by-election. In the other ruling, the EC decided that the Democrat Party did not violate the constitution by allying with banned politicians to form a government (the Constitution Court had already reached a similar conclusion).
               On 17 April, an unknown number of gunmen armed with military-grade automatic weapons attacked a small convoy of vehicles carrying People’s Alliance for Democracy leader Sondhi Limthongkul. Sondhi was injured, as were his driver and a close aide. The attackers fled. Police initially dismissed speculation that the military may have been involved in the attack, but it was then revealed that investigators found shell casings at the scene with Royal Thai Army markings indicating the bullets had been distributed to a unit in the First Army Region. Army chief Gen Anupong Paojinda acknowledged that the bullets appeared to be military, but insisted that they were training rounds and likely had been stolen; the military then refused to make any formal statements on the matter, saying that police had not made any formal request for information. Foreign Minister Kasit Piromya, speaking to the Asia Society in New York, accused Thaksin of being responsible for the attempt to kill Sondhi, saying, “Thaksin failed on the populist movement and now I think he has resorted to some sort of assassination attempt.” Kasit also claimed that he believes that four cabinet members were also targeted for assassination. He did not provide any evidence to support these claims. Conspiracy theories about the incident flourished: some claimed red-shirts may have wanted to eliminate the PAD leader in the hope of weakening or destroying the yellow movement; blue shirts may have tried in order to provoke PAD into fighting with the reds; the military may have wanted to provoke red-yellow fighting to create a pretext for a coup; the government may have wanted to get rid of Sondhi as a rival for influence; the incident may have been part of a business conflict, possibly aimed at destroying Sondhi’s media empire. Sondhi eventually accused rogue elements of the military of being behind the attempt to assassinate him though he added that he did not believe that the Royal Thai Armed Forces condoned the attack. Sondhi eventually made statements that the press interpreted as pointing at a woman, Viraya Javajul, who is seen as close to the military and the palace. Sondhi said he was targeted to intimidate the media and to undermine mass movements. He claimed that the attack was a signal to mass movement leaders—both yellow- and red-shirts—to disband.
               Puea Paendin party elected Industry Minister Charnchai Chairungruang as party leader, Charnchai was already serving as acting party leader. The election was necessary after the Election Commission nullified the election of Gen Pracha Promnok as party leader on grounds that the party did not inform the EC of the 9 December 2008 leadership election results within the 30-day deadline. Pracha’s faction did not attend the party general assembly. Puea Paendin is divided, with Charnchai’s faction of about 20 MPs supporting the government and Pracha’s faction, number about 12 MPs, aligning with Puea Thai in opposition.
               The Senate formed a committee to consider the qualifications of seven people nominated from among 133 applicants to serve on the National Human Rights Commission. (The terms of the first NHRC members lapsed on 12 July 2008, but political affairs have delayed selection of their replacements.) The committee quickly approved the seven candidates. Several prominent human rights figures, including Somchai Homla-or and Sriprapha Petchmesri complained that the selection process as non-transparent and had overlooked qualified and respected candidates; they also complained that the selection panel was composed of lawyers and state officials, and it appears to have selected like-minded people as candidates rather than genuine human rights advocates. 
               Attention and effort again turned to national reconciliation and constitution change. With this came renewed discussion of amnesty for currently banned former executives of political parties. Prime Minister Abhisit Vejjajiva said that he is willing to discuss amnesty, though the Democrat party appears to be divided on the issue; Democrat deputy leader Chalermchai Sri-on said that about 30 party members oppose constitution amendment to pardon banned politicians, among them former leader MP Banyat Bantadtan (former PM and current adviser Chuan Leekpai also spoke out publicly against the idea). Coalition partner Bhumjaithai Party (the vehicle of the Newin Chidchob faction) appeared to be divided on the idea of amnesty. Interior Minister Chaowarat Charnweerakul expressed the party’s support for amnesties, but Deputy Interior Minister Boonjong Wongtrairat has said that the party does not agree. Former Thai Rak Thai leader Chaturon Chaisaeng complained that the prime minister’s offer of political amnesty was not genuine, and instead was aimed at clearing People’s Alliance for Democracy leaders. People’s Alliance for Democracy figure Suriyasai Katasila expressed opposition to the idea of amnesty for politicians and amendment of the constitution, saying that such actions would only enflame the political crisis, and cause mistrust of the government’s political reform. A two-day parliamentary session held to find a solution to Thailand’s political conflict ended up as a forum for government and opposition to trade accusations of wrongdoing and responsibility for the violence over Songkran.
               Relations between Thailand and Cambodia were tense. In early April, Thai and Cambodian troops clashed twice in the area of Preah Vihear temple, reportedly leaving two Thai soldiers and two Cambodian soldiers dead and several injured. Despite some trading of accusations of blame, senior figures including Thai and Cambodian prime ministers responded calmly, and talks concerning the disputed temple area continued, though these failed to even produce agreement on whether to refer to the temple as Preah Vihear, as it is known to Cambodia and in World Heritage Committee proceedings, or Phra Viharn, the name used by Thai officials. Later, Cambodia reportedly demanded that Thailand pay US$2.15 million in compensation for damage caused to a market in March’s border clashes that left three Thai soldiers dead; Thailand refused, arguing that the incident took place on Thai soil, where some Cambodians were staying illegally. Adding to the tension were rumours of Thaksin Shinawatra holding a Cambodian passport and visiting Cambodia, allegations strongly denied by Cambodian officials.
              Over the course of April, violence in the South appeared to escalate, with several bombings and other attacks. Railway service was suspended for almost two weeks after suspected insurgents attacked a train in Narathiwat, killing a train attendant and injuring three other people (another attendant, a paramilitary ranger and a guard). Some violence was evidently orchestrated to coincide with the fifth anniversary of the Krue Se Mosque massacre, with at least 10 killings around that time. Authorities blamed insurgents, but local residents and some observers speculated that security forces or civilian anti-Muslim groups may have been responsible in at least some cases. The evident rise in violence came as Internal Security Operations Command announced that attacks had appeared to be on the decline over the previous six months.