Prime Minister Hun Sen ordered an investigation into the cause of the disaster.
Cambodia has declared Thursday a national day of mourning after at least 378 people were killed in a stampede in the capital, Phnom Penh, BBC reports.
Hundreds more were injured when people were crushed on a small island on the final day of the Water Festival.
The stampede took place on a bridge, which eyewitnesses said had become overcrowded. Prime Minister Hun Sen ordered an investigation into the cause of the disaster. Hun Sen described the stampede as the “biggest tragedy” to hit Cambodia since the mass killings carried out by the Khmer Rouge regime in the 1970s. He ordered all government ministries to fly the national flag at half-mast. The bridge crosses the Bassac River, which is being searched for more bodies of people believed to have drowned after falling into the water. Government spokesman Phay Siphan said the death toll could rise further, adding that 755 people had been injured.
Officials said most of the deaths were as a result of suffocation and internal injuries. No foreigners are said to be among the dead. Authorities had estimated that more than two million people would attend the three-day festival, one of the main events of the year in Cambodia. Panic broke out after a concert on Diamond Island, which followed a boat race on the Tonle Sap River regarded as a highlight of the festivities.
Sean Ngu, an Australian who was visiting family and friends in Cambodia, told the BBC too many people had been on the bridge. He said some of the victims were electrocuted.