Thailand's anti-government militants occupied Bangkok's international airport yesterday in a move to designed to provoke official retaliation and force a long-standing conflict to a head.

The militants of the People's Alliance for Democracy, who have occupied the prime minister's compound in central Bangkok since August, swarmed into Suvarnabhumi Airport airport late yesterday evening, meeting with little resistance.

The $4bn terminal,which is the gateway for the 13 million tourists who visit every year, was closed for outgoing flights shortly before the invasion.

An English-language website used by the militants said the PAD "expected to 'welcome' Prime Minister Somchai Wongsawat when he returns to Thailand later tonight". Mr Somchai, who has been in Peru for the APEC summit and is now expected to use another airport, has steadfastly attempted to ignore the PAD protestors, even relocating his offices to a disused airport rather than forcing them out of his compound.

Mr Somchai is the brother-in-law of ousted and exiled former Thai prime minister Thaksin Shinawatra, a telecommunications billionaire who is reviled by the militants as corrupt and manipulative.

"We want to seize the airport to show the media that the prime minister cannot control anything in Thailand," PAD supporter and retired government official Suwan Kansanoh told The Times. "He cannot control Don Muang airport [now the site of the prime ministerial offices]. They can do nothing. We've got the power to do anything."

Mr Suwan said he and about 25,000 of his fellow activists would hold the international airport until the PAD leaders told them to retreat. Some observers estimated there were only a few thousand largely unarmed militants occupying the site.

But although a few PAD guards had earlier fired on opponents elsewhere in Bangkok, injuring a number of people, the authorities have in the main favoured a policy of non-confrontation wherever possible.

Mr Suwan insisted the government had lost control of the police and the army. "I don't think they are listening to the deputy prime minister or the prime minister any more," he said. "They are not doing anything at the moment."

However, with six per cent of Thailand's gross domestic product directly dependent on tourism, it is unlikely the government will permit the airport occupation to last.

The action capped two days of PAD demonstrations, billed by the group's leaders as "the final mass rally to oust the nominee killer government". Yet the turnout for the final rally at Parliament House on Monday was thought to be about 20,000, a far cry from 2006 when the movement could send 100,000 militants onto the streets of Bangkok.

The PAD militants have tried to capitalise on public condemnation of police tactics, particularly following mass injuries and one death in early October when police fired exploding tear-gas canisters into a crowd of demonstrators. Yet public support for the ardently-royalist militants appears to be waning and PAD leader Chamlong Srimuang on the weekend declared that if this final push failed to topple the government "we will all go home".

General Anupong Paojinda, the army chief, yesterday said there would be no coup, even if violence erupted. "The armed forces have agreed that a coup cannot solve our country's problems and we will try to weather the current situation and pass this critical time," he said.

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