Thailand's embattled prime minister has invoked a special security law in the tense capital Bangkok and nearby areas after protesters stormed key ministries in a bid to topple the government.
The mass rallies against Yingluck Shinawatra and her brother, the ousted prime minister, Thaksin Shinawatra, are the biggest since 2010 when more than 90 civilians were killed in a bloody military crackdown.
But Ms Yingluck insisted the Government did not want to see a repeat of the violence that led to dozens of people being killed in a military crackdown, the BBC reports.
"Our national security service is now monitoring the protest and we are trying to handle the protesters without any violence," she said.
Special security measures would now be enforced in large parts of the capital, Nonthaburi to the north and areas to the east that included the airport, she added.
Amnesty irks protesters
Campaign leader Suthep Thaugsuban - a former opposition Democratic Party lawmaker - described the protesters' entry into government buildings as a "peaceful seizure by the people" so that the "Thaksin system can no longer work".
The demonstrators say the amnesty legislation would have allowed ousted leader Thaksin to return to Thailand without serving a jail sentence for corruption.
Thailand has been bitterly divided since Mr Thaksin was ousted in a military coup in 2006.
The amnesty bill failed to pass in the Senate earlier in November. But the proposal re-ignited simmering political divisions and raised the spectre of renewed political turmoil in the South East Asian nation.
Mr Suthep had said Monday's protest would be peaceful, with crowds "blowing whistles and handing out flowers".
The demonstrators marched to state offices, military headquarters and television stations.
But at the finance ministry, hundreds of people swarmed into the compound. The police were conspicuous by their absence. During the evening, they also moved into the grounds of the foreign ministry.
Two years after Mr Thaksin was ousted in 2006, groups opposed to him occupied Bangkok's main airport, shutting it down.
Then in 2010, those who backed him and his allies held two months of street protests that paralysed Bangkok.
Those demonstrations ended in a military crackdown. More than 90 people - mostly civilian protesters - died over the course of the two-month sit-in.
A government led by Mr Thaksin's sister was subsequently elected and since then Thailand has remained relatively politically stable.
Thaksin Shinawatra draws huge support from Thailand's rural poor but strong opposition from other sectors in society, and the divisions dating from the 2006 coup continue to dominate the political landscape.