PHNOM PENH, Cambodia — Cambodia's Parliament on Monday stripped the country's outspoken opposition leader of his immunity from prosecution for uprooting border markers on the frontier with Vietnam.

Opposition leader Sam Rainsy late last month led villagers in pulling out the markers as a way to dramatize his claim that Vietnam is encroaching on Cambodian territory, an issue he often raises to garner political support.

According to a statement from the National Assembly, prosecutors in the southeastern province of Svay Rieng are seeking to charge him with destruction of public property and inciting people to commit a criminal act. Provincial officials could not immediately be contacted to confirm the charges or what penalty Sam Rainsy might face.

All 87 members of the assembly present voted in a closed session to allow a lawsuit against Sam Rainsy. Sam Rainsy was in France, and the other 25 lawmakers from his party boycotted the vote.

Parliament is overwhelmingly dominated by the Cambodian People's Party of Prime Minister Hun Sen, an autocratic who tolerates limited dissent. Sam Rainsy is his perennial leading challenger.

In late June, two other Sam Rainsy Party members were stripped of their immunity so they could face defamation lawsuits filed by Hun Sen and senior military officers, respectively. Sam Rainsy in February also had his immunity temporarily lifted until he paid a fine for an electoral law violation.

"The event this morning is the beginning of the end of democracy in Cambodia. It is a sad day for us and for all Cambodians," said Son Chhay, chief whip of the Sam Rainsy Party. "The removal (of Sam Rainsy's immunity) was political intimidation, no doubt about that. This is clearly political abuse."

Son Chhay said that to show their solidarity, the party's other 25 legislators would ask the National Assembly to remove their immunity as well.

Sam Rainsy has claimed that he personally did not touch the six markers that were moved. The action attracted little attention until early November, when the Vietnamese government officially protested it.

Sam Rainsy, in a statement issued Saturday, said he had expected the assembly's action.

"It proves how subservient the Cambodian authorities are to the Vietnamese government," he said.

He charged that a much publicized dispute with Cambodia's western neighbour Thailand over a tiny patch of border jungle was meant to distract attention from Vietnam's alleged large-scale land encroachment.