According to Thai Defence Ministry spokesperson Surasant Kongsiri, fighting has been reported in at least six areas along the border. Videos have surfaced showing Thai villagers fleeing their homes to find safety as the clashes erupted in the morning.

The Cambodian provinces are just north of Siem Reap, a historic city globally famous for stunning temples such as Angkor Wat.

The warnings don’t extend to Siem Reap province itself but do cover several famous temples such as Preah Vihear, Ta Krabei and Ta Moan.

“Armed conflict between Thai and Cambodian military forces along the Thai-Cambodian border has increased,” Smartraveller warned.

“This includes reports of military strikes, violence and the use of landmines in the border areas.

“Follow the advice of local authorities, monitor local media for updates and pay close attention to your personal security.”

Thailand sealed all land border crossings while urging its citizens to leave Cambodia.

After assessing the situation, Smartraveller has advised Australians to reassess their travel plans to the Cambodian border provinces of Preah Vihear and Oddar Meanchey, as well as the adjacent Thai provinces of Buriram, Si Saket, Surin, and Ubon Ratchathani.

Longstanding disputes periodically flare along the 800-kilometre border.

They usually result in brief confrontations that sometimes involves exchanges of gunfire but relations have deteriorated sharply since a confrontation in May that killed a Cambodian soldier.

Yesterday’s clashes were far bigger in scale and intensity than usual.

– Reported with Associated Press