BANGKOK (Reuters) - Thousands of demonstrators massed outside four Thai government ministries, a major state office complex and 24 provincial halls on Wednesday in a widening effort to cripple the administration and oust Prime Minister Yingluck Shinawatra.

By evening, more than 13,000 protesters surrounded Thailand’s top crime-fighting agency and an adjacent government complex. They already occupy the Finance Ministry and have forced the evacuation of four other ministries in two days.

“We will stay overnight here. I urge all police to leave this compound,” protest leader Suthep Thaugsuban told reporters outside the Department of Special Investigation, the country’s equivalent to the U.S. Federal Bureau of Investigation.

The protests threaten to destabilize Thailand at a delicate time, just as its $366 billion economy, Southeast Asia’s second biggest, is losing momentum. Data released on Wednesday showed exports fell 0.7 percent in October from a year before, worse than the 0.7 percent rise most economists had expected.

Responding to the crisis, Thailand’s central bank unexpectedly cut interest rates by a quarter point at its policy-setting meeting.

The demonstrators, a motley collection aligned with Bangkok’s royalist civilian and military elite, accuse Yingluck of being an illegitimate proxy for her billionaire brother, former Prime Minister Thaksin Shinawatra, a populist hero of the rural poor who was ousted in a 2006 military coup.

Most of the 24 provinces where demonstrators had massed are in the south, a traditional stronghold of the opposition Democrat Party, although four were in the north and northeast, where the Shinawatra family is hugely popular.

The aim of Wednesday’s rallies was to wipe out the “political machine of Thaksin”, said Suthep, a former deputy prime minister under the military-backed government that was routed by Yingluck in a 2011 election.

The DSI recently indicted Suthep, and former prime minister Abhisit Vejjajiva, for murder for their alleged role in the deaths of more than 90 people in 2010 when troops crushed protests by Thaksin’s supporters.

“This department is supposed to be an independent organization, but it has not acted neutrally,” said Chattavorn Sangsuwan, 38, a demonstrator and employee at a car firm. “We will finish off what the coup-makers started in 2006. Their job was not complete, Thaksin’s influence is still everywhere. We are here to finish the job.”

“WILL NOT USE FORCE”

A short walk from the Department of Special Investigation, several hundred protesters streamed into a government office basement. There was no security and the mood was festive. Families with babies in strollers, their faces painted in the red, white and blue stripes of the national flag, roamed the manicured lawns of a nearby government complex.

About 3,000 people also gathered at the Energy Ministry, 700 at the Commerce Ministry and 200 at the Industry Ministry, police said. Provincial rallies ranged from 20 people in Narathiwat to 4,000 in Surat Thani, Suthep’s political base.

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Interior Ministry Permanent Secretary Wiboon Sagnuanpong told Reuters all ministries were still operating.

At the besieged Finance Ministry in Bangkok, protesters slept on plastic sheets in its grand reception area. Some bathed in the well-kept garden or hung laundry from its plants.

The protests are all-too familiar in Thailand, which has seen eight years of on-off turmoil, from crippling street rallies to controversial judicial rulings and army intervention, each time with Thaksin at the centre of the tumult.

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Despite fleeing into exile to dodge a jail sentence for abuse of power in 2008, billionaire former telecommunications mogul Thaksin has loomed large over Thai politics.

He won the support of the rural poor who voted him twice into office, in 2001 and 2005, before he was ousted in a 2006 coup. His supporters remain fiercely loyal to him and swept Yingluck to power in an election landslide in 2011.

The anti-government protesters, led by Suthep, chanted abuse at the DSI as scores of riot police donned helmets and held up shields, as crowds pushed against a low fence. Some employees were seen leaving their offices and joining the demonstrations.

Thaksin’s opponents are fewer in number than his supporters but hold considerable power and influence, among them wealthy conservatives, top generals, bureaucrats, royalists and many members of the urban middle class.

Many of them see Thaksin as a corrupt, crony capitalist who manipulates the masses with populist handouts and is a threat to the monarchy, which he denies.

The anti-government campaign started last month after Yingluck’s ruling Puea Thai Party tried to pass an amnesty bill that critics said was designed to absolve Thaksin of his 2008 graft conviction.

The protests, though peaceful, have raised fears of unrest. Anti-government protest leaders, from all sides, have a tradition in Thailand of trying to provoke a violent crackdown by the government to rob it of legitimacy.

Fearing clashes could erupt and further weaken her government, Yingluck said police would keep the peace.

“My government will not use force. This is not the ‘Thaksin regime’, this is a democratically elected government,” Yingluck told reporters outside parliament, where she is being grilled by opposition lawmakers in a two-day confidence debate.

Business leaders are watching closely.

True Corp Pcl said it was pressing ahead with an initial public offering for its infrastructure fund that may have a market value of about 70 billion baht ($2.1 billion), though market players have said the country’s largest integrated telecoms firm will have to price the deal attractively given the political tension.