PHNOM PENH - Cambodian Prime Minister Hun Sen said Thursday that the government will not forgive anyone who attempts to cause chaos to social security and urged the peoples to continue supporting him to maintain the country's hard-won peace.

"Peace brings us survival, no fear of war, development and poverty reduction, so we all must maintain it at any cost," he said in a speech during the opening ceremony of the Angkor Sankranta festival in northwestern Siem Reap province.

"We will not tolerate anyone who attempts to cause a split, to incite chaos in the society," he said, calling on the Cambodian peoples to join him to maintain the country's peace and stability.

His remarks came after the government arrested opposition lawmaker Um Sam An on Monday for posting messages and video clips to his Facebook page, accusing the government of using fake border map with Vietnam.

The Phnom Penh Municipal Court on Tuesday charged the lawmaker with two counts -- inciting social chaos and discrimination -- which could face up to five years in prison if convicted.

In August last year, opposition senator Hong Sok Hour was also arrested for posting a fake version of a Cambodia-Vietnam border treaty on a Facebook page.

He was charged with falsifying public document, using the fake document, and inciting chaos to social security, which could carry a maximum jail term of 17 years if convicted.