This is the dramatic moment Thai pupils evacuated their school as gunshots were heard near the Thai-Cambodia border.

Footage shows panicked children and their teachers fleeing from the school building after gunfire broke out at the edge in Si Sa Ket province on Tuesday.

They temporarily stayed at the covered court of Bueng Malu Witthaya School before being sent home to their families.

The 2nd Army reported that four Cambodian soldiers approached the barbed wire fence and fired three rifle shots at a military outpost at 1:22 pm local time.

It said in a statement: 'Thai troops exercised restraint, did not return fire, and no casualties or damage were reported.

'This deliberate action constitutes a clear violation of the military ceasefire agreement and demonstrates the Cambodian military's lack of sincerity in honouring the commitments jointly signed at the General Border Committee and Regional Border Committee meetings.'

Tensions are high in border provinces after protests from the Cambodian side broke out last week, in the worst escalation since a military ceasefire was brokered by ASEAN members in July.

Thai riot police fired tear gas and rubber bullets at the civilians who were trying to tear down razor wire fences and hurling insults at the officers.

Cambodian officials claimed 23 villagers were injured, while the Thai authorities said several troops were also wounded.

Thailand has since given Cambodia 30 days to clear the area if no agreement is reached after the next General Border Committee talk.

Thailand and Cambodia have been fighting for more than a century over several undemarcated sections of their 817-kilometre (508-mile) border, which was originally mapped by France in 1907 while Cambodia was still its protectorate.

But tensions flared in the long-disputed frontier as both accused each other of instigating violence on July 24, which killed at least 48 and temporarily displaced some 300,000 on both sides of the border.

Cambodia claimed responsibility for the alleged war crime of firing rockets into Thailand that struck a gas station, killing a number of children.

The two nations have reached a shaky truce following talks facilitated by Malaysian Prime Minister Anwar Ibrahim, chair of the Association of Southeast Asian Nations (ASEAN).