Thailand's government yesterday urged police to arrest opposition protest leaders who have threatened to take the prime minister captive and paralysed parts of central Bangkok. Officials said the demonstrators' self-styled "shutdown" of Bangkok, aimed at forcing Prime Minister Yingluck Shinawatra from office, appeared to be losing momentum with a dwindling number on the streets. Leaders of the anti-government movement travel freely around the city delivering fiery speeches and collecting money from supporters, despite warrants for their arrest for their roles in civil unrest that has left eight dead and hundreds injured. Rally leader Suthep Thaugsuban faces an insurrection charge - in theory punishable by death - in connection with the protests, as well as a murder charge linked to a military crackdown on opposition protests that left dozens dead when he was deputy premier in 2010. "It's the duty of the police to arrest Suthep because he is wanted for insurrection, otherwise police will face malfeasance charges," Deputy Prime Minister Surapong Towijakchaikul said after a meeting the national police chief. Surapong said Suthep, a former opposition MP, was protected by about 40 personal bodyguards. Some observers believe the veteran political power broker is unlikely to go to jail as he enjoys the support of the kingdom's royalist establishment. The protesters want Yingluck's popularly elected government to resign to make way for an unelected "people's council" that would oversee reforms to curb the political dominance of her billionaire family. National Police Chief Adul Saengsingkaew said 7,000 protesters were estimated to remain on the streets yesterday morning, down from 23,000 the previous evening. Turnout tends to rise when people leave work. Yingluck's supporters say the rallies are a threat to the country's fragile democracy and want the dispute to be settled at the ballot box, but the opposition is boycotting a February 2 election.