Supporters of an anti-government movement seized a government-run television station Tuesday and forced it off the air in what they called their final showdown with Thailand's current administration.
People's Alliance for Democracy (PAD) supporters seized the National Broadcasting Service of Thailand (NBT) in Bangkok and have demanded Prime Minister Samak Sundaravej and his cabinet step down, the dpa reported.
Police Tuesday morning threatened to arrest PAD leaders Sondhi Limthongkul and Chamlong Srimuang, but had yet to do so.
Earlier Sondhi called Tuesday "the last whistle blow" in their efforts to topple Samak's government.
PAD protesters were gathering in strategic parts of Bangkok to have maximum impact, including surrounding government house to prevent the holding of the weekly Tuesday cabinet meeting.
Samak told local media they would hold the meeting elsewhere away from the protesters.
The PAD organized months of protests against former prime minister Thaksin Shinawatra, who was ousted in a bloodless coup in September 2006 for undermining the monarchy, among other charges.
With Sondhi's backing, the PAD now is trying to bring down the government of Samak, a political ally of Thaksin.
The PAD has been calling for Samak's resignation for the past months after the government approved a motion to amend the 2007 constitution.
Protest leaders claim the amendments are aimed at clearing Thaksin of corruption charges and paving the way for his return to power.
Thaksin, a billionaire businessman, used populist policies to claim the premiership between 2001 to 2006, winning himself a huge following among Thailand's poor but turning the political elite against him when his growing monopoly on power led to perceived abuses for his personal gain.
After spending 17 months in exile in the post-coup period, Thaksin returned to Thailand in February but fled again this month.
He is now seeking asylum in England.