At least nine school pupils have died in southern Cambodia after the boat they were travelling in capsized, officials said.

Four people – two students and two of the boat’s crew – were rescued following the accident on Thursday night on the Mekong River south-east of Phnom Penh, and two students were still missing on Friday, police said.

Major General Chhoeun Sochet, chief of the Kandal provincial police, said on his Facebook page that the ferry was overloaded and carried no life jackets.

The students, who were between 12 and 14 years old, lived on an island in the river and used the ferry for transport almost every day in the rainy season, as did others from their village.

During the dry season, the river has little or no water and can be traversed by foot.

The students were on their way to an English class on Thursday when the boat capsized.

The accident occurred near the Neak Loeung bridge over the Mekong, which at that point separates Kandal province on the western shore from Prey Veng on the east.

The bridge is part of Route 1, a major road connecting the capital, Phnom Penh, to Ho Chi Minh City in neighbouring Vietnam.

The police chief in Kandal’s Leuk Daek district, Am Thou, said the accident occurred as the boat was approaching the shore. It took on water in the bow, and the students were instructed to move to seats in the middle or stern of the boat.

However, as they walked back, the boat became unbalanced and turned over.

One of the survivors, 12-year-old Ry Chanbora, was shown in a video broadcast online by Swift News telling relatives that she normally does not know how to swim well despite living near the river.

She said that when the boat was going down she jumped out, trying to swim with her face up, and drifted to the river’s bank.

Provincial officials paid a visit to the girl, and King Norodom Sihamoni on his royal Facebook page offered condolences and prayers for the families of the victims.

Police chief Am Thou said the boat’s owners, who were its crew, had been taken to hospital after the accident but would face legal action. He did not say what charges they would face.

The World Health Organisation said last year that according to assessments in 2019, more than 144,000 drowning deaths occurred in the Asia Pacific region, 61% of the global total.

“Of the 70,000 drowning deaths in the WHO South-East Asia Region in 2019, more than 33% were among children aged under 15 years,” said the UN agency.

“On average, men were three to four times more likely to drown than women.”