A schoolteacher and three of her students were injured this morning after an unexploded 60mm mortar round was set off by a nearby garbage fire on their school’s grounds in Oddar Meanchey province.

The teacher and students are from the province’s Hun Sen Anlong Veng Primary School.

“They were sent quickly to Oddar Meanchey [Provincial] Hospital for treatment by the local authorities and armed forces, and now they are being treated,” Anlong Veng Commune Chief Vong Pheak said.

Pheak added that teacher Hun Maly, 34, and student Chhorn Srey Em, 14, received minor injuries, whereas Hour Polin, 13, and Hoem Sokly, 10, had more serious injuries.

Police officials investigating the scene found fragments of a 60mm mortar round, and concluded that it exploded due to the heat from a fire above it.

“I think that it was underground and it exploded when they dragged the garbage and firewood to burn on top of it,” said Sim Vannak, Anlong Veng district police chief said.

Cambodia’s western provinces are still riddled with unexploded ordnance left over from decades of civil war. As of June, the most recent month for which statistics are available, Oddar Meachey had seen 19 unexploded ordnance accidents since the beginning of 2016, 10 of which occurred in 2017, accounting for nearly a fifth of all accidents and casualties across the country.