At least eight Vietnamese were killed in Cambodia's water festival stampede which left more than 350 people dead, according to an association of Vietnamese people in Cambodia.
Trinh Viet Long, an official from Vietnam Embassy in Cambodia, said among the dead was Nguyen Van Cu, a 12-year-old boy, while others have not been identified.
There were five other Vietnamese missing and eight injured, Long said. All of the victims were all from districts around Phnom Penh, he said.
Many Vietnamese people in Cambodia were worried as they have failed to contact relatives who left home over the weekend to attend the water festival called Bon Om Thook held between November 21 and 23.
The association has sent representatives to communes near Phnom Penh to get more information.
Following the incident, several tour operators in Ho Chi Minh City such as Fiditour and Lua Viet have delayed tours to Cambodia.
Panic ensued and around 350 people were trampled to death on Koh Pich bridge after a rumor spread that the narrow bridge was unstable, Cambodian government spokesman Khieu Kanharith told AFP.
The festival-goers had been crossing the bridge to reach an island hosting concerts, food stalls and ice sculptures.
Many of the deaths were caused by suffocation and internal injuries and about two-thirds of the dead were women, Kanharith said.
More than 400 people were injured.
Witnesses said there were people jumping and falling into the river below the bridge, so authorities are also searching for bodies in the water.
Prime Minister Hun Sen described the disaster as Cambodia's darkest hour since the Khmer Rouge, whose 1975-1979 reign of terror left up to a quarter of the population dead.
Hun Sen said Cambodia would hold a national day of mourning on Thursday.
The bodies have been laid out in hospitals around the capital for relatives to identify them.
The annual festival, including boat races, concerts and fireworks, marks the reversal of the flow between the Tonle Sap Lake and the Mekong River in a natural flushing motion.