At least eight schoolchildren have died after a ferry they were riding sank in Cambodia on Thursday evening.

The pupils were headed home to an islet in Koh Chamroeun village in Kandal province when the vessel sank due to heavy rain causing choppy waters on October 14, authorities said.

Rescuers battled to save the youngsters, shining lamps on murky waters along Kampong Dor Toteung as they launched a frantic search operation at night.

Divers wearing oxygen masks also plunged into the river hoping to find the missing kids.

The search and rescue continued until Friday morning as anxious villagers watched and waited along the banks.

Kandal Provincial Police said eight students had drowned while four others were found alive as of October 14. Four more are still missing.

Kandal Provincial Police Commissioner Major General Chhoeun Socheth said: 'The incident happened when the children boarded the boat leaving the school. They were going home to Koh Chamroeun village.

'The water levels in the river started rising because of heavy rains.'

The search for the missing children is still ongoing.