Landmine dispute escalates tensions between Thailand and Cambodia

BANGKOK (Reuters) -Thailand has accused Cambodia of recently placing landmines in a disputed border area after three soldiers were injured, but Phnom Penh said they had veered off agreed patrol routes and triggered a mine left behind from decades of war.

Thai authorities made the claim after three soldiers were injured, with one losing a foot, by a landmine explosion while on a routine patrol on July 16 on the Thai side of the disputed border area between Ubon Ratchathani and Cambodia's Preah Vihear province.

Cambodia's Defence Ministry denied that new mines had been planted, saying in a statement on Sunday the soldiers had strayed from agreed patrol routes into areas that contain unexploded landmines. The country is littered with landmines laid during decades of war.

Thailand's army said on Monday that 10 freshly laid Russian-made PMN-2 type landmines, which are not used or stockpiled by Thailand, were found between July 18 and July 20 in areas near where the soldiers were injured.

"This is a clear violation of the sovereignty and territorial integrity of the Kingdom of Thailand and an outright breach of principles that are fundamental to international law," Maratee Nalita Andamo, deputy spokesperson for the Thai Foreign Ministry, said on Monday in Bangkok.

Data from the Cambodia Mine Action Centre, which estimates there are still 4 to 6 million landmines scattered across the country, shows five people were killed and a dozen injured by mines and unexploded ordnance in Cambodia in the first four months of 2025.

The area where the mine exploded is near where a Cambodian soldier was killed in May after a brief exchange of gunfire between troops on both sides.

The incident has flared into a broader diplomatic dispute between the Southeast Asian neighbours that has destabilised the Thai government and seen the Prime Minister suspended from office.

Thailand said it will issue a formal condemnation and call for accountability from Cambodia for breaching the anti-landmine convention under the Ottawa Treaty, and the army will also increase vigilance during border patrols.    

(Reporting by Panu Wongcha-um and Panarat Thepgumpanat; Editing by John Mair)