Bangkok's deputy police chief said Friday that 21 leaders of the royalist Yellow Shirts would be charged with unlawful gathering, leading to the seizure of Government House last October during a series of protests aimed agains the then government.
Metropolitan police Major General Amnuay Nimmano said the leaders of the yellow-shirted People's Alliance for Democracy (PAD) - allies of the current government - would also be charged with obstructing the work of the authorities, reported dpa.
The Yellow Shirt protestors succeeded in paralyzing the previous government by taking over Government House and, later, Bangkok's two international airports.
Leaders of the PAD include prominent activists Sondhi Limthongkul, Somkiart Pongpaiboon and Suriyasai Katasila.
Foreign Minister Kasit Piromya was also leader of the PAD and is a target for supporters of former prime minister Thaksin Shinawatra, who are demanding his resignation.
However, Amnuay said there was no evidence Kasit was involved in taking the cabinet buildings on that day. The police investigation into the airport seizures were 80 per cent complete, the Bangkok Post newspaper said.
The takeover of Government House and the airports helped bring down a government backed by self-exiled Thaksin, but also irritated rural and poor voters supported him. His ruling party was dissolved by a Constitutional Court ruling on December 3, which found it guilty of committing fraud in the last polls.
The ruling paved the way for the Democrat Party of Prime Minister Abhisit Vejjajiva, which came in second place in the 2007 polls, to form a new coalition government.
Pro-Thaksin Red Shirts insist the Democrat-led government lacks legitimacy since the Democrats did not win the largest number of seats in the last election.
The current government is in the awkward position of owing much to the Yellow Shirts - named after their habitual royalist yellow attire - but needs to acquire legitimacy by demonstrating adherence to the law.
The Red Shirts abandoned their own three-day protest outside Government House in the early hours of Friday after vowing to continue their campaign to bring down what they call an illegitimate administration.
Thaksin was ousted by a military coup on September 19, 2006, but his political allies returned to power in the guise of the newly created People Power Party which won the December 23, 2007, general election. He is in self-exile to avoid a two-year jail sentence over a corrupt land deal involving his wife.
Thailand appears likely to be hard hit by the global economic crisis so the economic cost of the week-long airport closures may come back to sting the government if it is seen as too closely associated with the Yellow Shirts.
Thaksin is scheduled to speak at Hong Kong's Foreign Correspondents Club Monday, which observers say is a provocative move. Abhisit said the government was exploring legal options of extradition now that it appears to have a definite fix on Thaksin's whereabouts.