A farmer preparing a plot of land for a vegetable garden found a cache of unexploded 60mm mortar rounds from the 1970s on the campus of a secondary school in Pursat province’s Kandieng district over the weekend.

After the farmer uncovered 24 shells, experts from the demining NGO HALO Trust called to the site found another 117 mortar rounds on Sunday evening, said Buth An, a Kandieng district police officer in charge of explosives.

The demining team safetly detonated 89 rounds, An said. Sman Makara, HALO Trust’s head of ordnance, said his team will return to Plov Luong commune to detonate the remaining 52 in the next few days.

“Those ordnances are made in the US and left from the war in the 1970s,” Makara said.

Kangan Secondary School principal Chhut Chhun said he had been “really scared” when the unexploded ordnance was found on the school campus.

“However, it is very fortunate that those ordnances do not explode, or else I cannot imagine how many teachers and students will be injured because of them,” Chhun said.

Last month, one teacher and three students in Oddar Meanchey province’s Anlong Veng district were injured after a 60mm mortar exploded while teachers were burning trash on campus.