Thai protesters have entered the government's headquarters after police removed barricades from outside both Government House and the police office, the BBC reported. The mood in the capital Bangkok appeared considerably calmer after the move, which followed clashes over the weekend and on Monday. But as tensions fell, protest leader Suthep Thaugsuban vowed to fight on and remove the government. The Thai prime minister has rejected protesters' demands that she step down. Yingluck Shinawatra said she was open to negotiations but that calls for the government to be replaced by an appointed council were illegal and unconstitutional. The protests, which began on 24 November, had been largely peaceful until Saturday, when they became violent. Over the weekend and on Monday demonstrators tried to break apart police barricades and storm the prime minister's office, Government House, with police using tear gas and water cannon to repel them.