Thailand must withdraw all military and police forces from the area surrounding a 900-year-old Hindu temple on the far side of its border with Cambodia, UN judges have said in a ruling that could exacerbate tensions between the two countries.
The judges ruled on Monday that the promontory on which the Preah Vihear temple sits was part of Cambodia.
The court awarded the temple itself to Cambodia in a 1962 judgement, but Thailand had maintained that ownership of the rest of the hilltop - a 4.6-square km section of land - had not been settled.
"The court unanimously declares that Cambodia has sovereignty over the whole of the territory of the promontory of Preah Vihear," said Peter Tomka, president of the International Court of Justice.
We have already prepared our bunkers in case Thai troops open fire.
Tension had been running high and dozens of Thai schools had closed ahead the ruling.
At least 28 people have been killed in outbreaks of violence since 2011 over who owns the patch of land adjacent to the 900-year-old Preah Vihear temple.
Tens of thousands of people were displaced in the fighting, leading Cambodia to ask the ICJ for an interpretation of an original 1962 ruling.
The mood on both sides of Preah Vihear temple was tense early on Monday, with tourists still allowed to visit the ancient structure through Cambodia. Journalists were denied access.
Al Jazeera's Scott Heidler, reporting from the Thai side of the border, said that some members of the community were gathering in a local hall to watch the ruling so that they could discuss their reaction to it.
"They're bracing for the worst," Heidler said. "This is something that they've gone through time and time again."
Al Jazeera's Rob McBride, reporting from the Cambodian side of the border, said there was a feeling among the people there that the ruling would go thier way.
"Nonetheless, people are preparing for anything that should take place," McBride said.
Local residents on both sides said they were taking no chances and some Cambodian residents even dug bunkers in anticipation of violence.
"We have already prepared our bunkers in case Thai troops open fire," So Phany, a vendor near Preah Vihear temple, told the AFP news agency.
Some local media reports said Cambodia had sent military reinforcements to the area, but army sources declined to comment.
On the Thai side, about 40 primary schools were closed in one district on the border on Monday, according to a provincial education official, Somsak Chobthamdee.
Thai Prime Minister Yingluck Shinawatra vowed on Sunday to "consult" with Cambodia after the decision to avoid any conflict.
In a televised address, her Cambodian counterpart, Hun Sen, meanwhile urged for restraint in order to avoid any upheaval of violence.
Both have vowed to abide by any ICJ ruling.