Seven Cambodian girls, aged between six and 13-years-old, drowned on Tuesday morning when their small wooden boat capsized in a lake in the seaside town of Sihanoukville, police said.
The girls were among nine local children enjoying a rowing excursion, Chuon Narin, police chief of Kampong Som province, told AFP.
"They often played at the lake and this time they boarded a small wooden boat. But it was unsteady and capsized," he said.
Another girl and a boy were saved and sent to hospital, Chuon Narin said.
"It is tragedy, this is very sad," he added.
Local media ran pictures of desperate, tearful relatives mourning over the bodies of the little girls.
Cambodian children who live near water usually learn how to swim from an early age. It was not clear whether the victims were strong swimmers.