Thailand on Monday carried out airstrikes along its disputed border with Cambodia, Bloomberg and Reuters report.

The incident occurred after the two countries accused each other of violating the ceasefire agreement signed with US President Donald Trump’s mediation.

According to a Thai military statement, at least one Thai soldier was killed and four others were wounded during new clashes that broke out in two districts of Ubon Ratchathani province in the east. This happened after Thai troops came under fire from Cambodian forces.

Bloomberg reports that, according to the Thai military statement, Cambodian forces opened fire on several border areas using small arms, machine guns, mortars, and artillery.

They added that the response actions, which included ground fire and air operations, were taken in accordance with international regulations to protect sovereignty, and noted that the actions were intended to prevent further attacks and a wider escalation.

The Thai side has begun using airstrikes against military targets in several areas, the statement added.

For its part, Cambodia’s Ministry of National Defense claims that after several days of provocative actions by Thai forces, they struck Cambodian positions in two locations in the morning, and added that Cambodian troops did not take any retaliatory measures.