Thailand accused Cambodia of planting new land mines on the Thai side of the shared border, in an escalation of a bitter territorial dispute between the two countries.

Three Thai soldiers were injured when they stepped on a land mine during a routine patrol along an established route within Thai territory on July 16, the Ministry of Foreign Affairs said in a statement late Sunday. The mines were not of a type used by Thailand and were recently laid in a "blatant violation of international law,” it said.

"The Royal Thai Government condemns in the strongest terms the use of anti-personnel mines,” the ministry said, adding that it planned to take action against Cambodia under the United Nations’ Anti-Personnel Mine Ban Convention as a state party while pursuing bilateral channels to resolve the ongoing dispute. "Thailand calls on Cambodia to cooperate on humanitarian demining efforts along the border of the two countries as bilaterally agreed by both Prime Ministers.”