Bangkok police Tuesday removed concrete barriers and barbed wire from around their headquarters to allow protesters inside the compound, in an apparent move to avoid a confrontation, dpa reported.
Protest leader Suthep Thaugsuban in a speech Monday night directed his followers to occupy the Metropolitan Police Bureau in western Bangkok, which has been targeted by protesters since the weekend.
"Everyone can enter the bureau," the bureau's commissioner Police Lieutenant General Khamronvit Thupkrajang told reporters. "The bureau is the property of the people."
Khamronvit promised that police would not use tear gas on the protesters, who are seeking to occupy various government offices in a bid to paralyze the administration of Prime Minister Yingluck Shinawatra.
Police did use tear gas to push back protesters early Tuesday from Government House, the seat of the administration, but some barriers there were also subsequently taken down, witnesses said.
Since Sunday, increasingly violent clashes between police and protesters have left 119 injured, the Erawan Medical Emergency Centre said.
At least three people died and about 60 were injured over the weekend, according to government figures, after anti- and pro-government groups clashed in the east of the capital.
On Monday, the Criminal Court issued a warrant for the arrest of Suthep on charges of insurrection, which is punishable by death.
Pamphlets announcing the arrest warrant for Suthep were dropped on a protesters' camp near the police bureau early Tuesday.
Suthep has urged his followers to fight to the finish.
Analysts said Yingluck was counting on attrition to undermine the protest, after their failure to capture key installations over the weekend.
"I think the government hopes that Suthep's forces are going to whither away," said Chaiyan Rajchakool, a political scientist at Ubon Ratchathani University, in north-east Thailand. "They will rely on time to tire them out."