The fragile calm along the Thai-Cambodian border has been shaken once more after Thai forces fired rubber bullets and tear gas at a group of Cambodian protesters, an incident that both sides claim reflects violations of their July ceasefire agreement.

What began as routine military work by Thai personnel in Sa Kaeo province quickly escalated when around 200 Cambodians gathered to protest the laying of barbed wire. According to Bangkok’s military, the crowd threw rocks and other objects at soldiers.

"It became necessary to use tear gas and rubber bullets to control the situation, and make the crowd pull back from the area," the Thai army said in a statement. Officials later accused Cambodia of failing to prevent the protesters from entering Thai soil, calling it “a provocation which is a violation of the ceasefire.”

Phnom Penh countered that the confrontation occurred inside Cambodian territory in Banteay Meanchey province. Cambodia’s information minister Neth Pheaktra reported that 23 people were injured, among them a soldier and a Buddhist monk. “This is a breach of the ceasefire by the Thai side,” he said.

Video clips circulating online showed villagers carrying long sticks while facing lines of Thai authorities equipped with riot shields. In one clip, a monk and several men attempted to remove barbed wire before uniformed soldiers responded with tear gas.

The flare-up is the first recorded use of tear gas or rubber bullets along the border since July’s truce, which had halted five days of clashes that left at least 43 people dead and forced 300,000 residents to flee. At the heart of the long-running dispute are contested temples straddling the 800-kilometer frontier.