At least 84 Thai Muslims died -- mainly from suffocation in the back of packed security force trucks -- after police and troops broke up a violent demonstration in the kingdom's troubled south, Thai officials said.
Most of the victims suffocated when 1,300 detained protesters were crammed into trucks after officials used water cannon and tear gas to break up a protest Monday outside a police station in Narathiwat province.
Six were confirmed dead from the clashes on Monday. The others were crushed and suffocated, including several with broken necks, as they were taken away in the trucks for questioning, according to officials.
"After we brought people who were arrested into detention, we found that another 78 people were dead," Manit Suthaporn of the justice ministry told reporters.
He said the detainees were piled on top of each other in the back of the trucks. "According to the investigation of the dead bodies, they died because of suffocation," he said.
Prime Minister Thaksin Shinawatra, speaking before the announcement of the 78 deaths, said the protesters were weak because of fasting during the holy month of Ramadan which started on October 15.
"It is normal that their bodies could not handle it. It is not about someone attacking them," Thaksin told reporters.
The protests were sparked by the arrest of six Muslim men accused of handing guns to rebels in Muslim-majority southern Thailand, where an insurgency has left 414 dead this year. Police said some of the crowd on Monday tried to storm the police station but were stopped by the 1,000-strong security force.
The detainees were lined up face down on the ground in a row, with their hands tied behind their backs before being taken away in trucks.
Thai forensic scientist Pornthip Rojansunan told a press conference in Pattani province that 80 percent of the victims died because they could not breathe.
"We didn't find any dead bodies with broken arms or legs, but between two or three of them had broken necks which may have been caused from the transportation," she said.
Government spokesman Jakrapob Penkair said earlier that "fasting and possible drug consumption" were the major factors behind the deaths.
Rights activists have previously accused the authorities of heavy-handed tactics in the south, including the storming of a mosque that left 32 Muslim militants dead during a one-day uprising in April.
The insurgency in the south of mainly Buddhist Thailand has continued sporadically for decades and sparked into life again in January with a raid on an army depot.
Abdul Rahman Abdul Samed, the top Muslim official in Narathiwat, told AFP he feared the incident could spark a violent reaction.
"I am concerned that the incident yesterday will escalate the tension in the south and some groups may try to do something about taking revenge," he said.
His deputy condemned the government's comments about the effect of fasting for Ramadan. "They are youths, they should not have any problem," said Abdul Rosa Aree.
"I think the government is too fast to conclude what caused their deaths."
A member of Thailand's state-backed human rights commission also warned earlier of worsening violence and said the break up of the demonstration was "clearly a violation of people's rights".
"We are concerned that the situation will get worse as families of people who died and were injured may not understand the actions of the authorities," said Amporn Meesuk.
Police said the situation was under control on Tuesday after the biggest clash between authorities and disaffected Muslims since a day-long uprising in April left 113 people dead.
Interior Minister Bhokin Bhalakula told reporters in Bangkok early Tuesday the demonstrators were Thai Muslims who "don't respect the law and their religion. They made trouble while authorities tried to do everything to stop it".
Malaysia Prime Minister Abdullah Ahmad Badawi was quoted as saying he was very concerned by the crisis.
"If there is anything that we can do to help, we will. If not, we wish that the Thai government will be able to manage this crisis so that it will not spread and cause further violence," Abdullah told Bernama news agency.