Thailand sank deeper into political chaos yesterday as anti-government demonstrators forced the closure of airports and railway lines, stranding foreign and domestic passengers and increasing fears of yet another military coup.

In the capital, Bangkok, a crowd of 2,000 people faced a barrage of teargas as they attempted to take over police headquarters. In other parts of the country, members of the People’s Alliance for Democracy (PAD) demanding the resignation of Prime Minister Samak Sundaraveg shut down airports in Hat Yai and the tourist resorts of Phuket and Krabi.

“This is embarrassing in front of the world,” Mr Samak said, three days after being forced out of his office by demonstrators. “I have several tools at my disposal, but I am not using any of them because I want to keep things calm. I will not quit. If you want me out, do it by law, not by force.”

According to Thai newspaper websites, striking railway workers brought a halt to trains, and unions were urging airline and railway workers to take “sick leave” in support of the protests — the most serious political crisis since a military coup that deposed Thaksin Shinawatra, the former Prime Minister, two years ago.

The confrontation began on Tuesday when supporters of the PAD — which, despite its name, advocates an end to a democratic system — raided a state television station, government buildings and the compound containing the Prime Minister’s office. They have barricaded themselves behind razor wire and car tyres.

Their resources and the seeming reluctance of the police to act suggests that the protesters may have influential supporters in the army or the royal establishment. PAD supporters wave pictures of the King, Bhumibol Adulyadej, reading “We love the King. We love Thailand”.

“We definitely won’t leave the Government House until we can topple Samak’s administration,” the PAD leader, Sonthi Limthongkul, said. “He cannot stay on for long, I am very sure of that.”

Mr Samak was elected last December after the general election victory of his People Power Party (PPP), and made no secret of his loyalty to Mr Thaksin, the most popular, but most divisive, Prime Minister in Thailand’s history.

Mr Thaksin was deposed in the military coup in 2006 and went into exile in London, where he became proprietor of Manchester City Football Club.

This week’s demonstrations may, however, represent a last hurrah by the PAD, which has lost support among ordinary Thais for its confrontational tactics.

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