The evacuation of thousands of tourists stranded in Thailand began yesterday from an airfield at a Vietnam Warera naval base.

Antigovernment protesters, clad in yellow T-shirts and waving placards, continued their blockade of Bangkok’s two main airports, preventing flights in and out of the country.

As the day wore on there was a build-up of riot police and armed officers a few hundred metres from the terminal building at Suvarnabhumi, the main airport. At least 120 officers, three police trucks and 14 ambulances arrived as a police helicopter hovered overhead. The number of protesters also swelled steadily into the thousands.

Harry Denford, a British tourist stranded with about 2,000 other holidaymakers in the resort town of Pattaya, feared that the People’s Alliance for Democracy (PAD) activists would prevent their evacuation.

“We were told the yellow shirts were coming,” Mr Denford said. “I don’t know if they will be able to take over the [naval] base or not.”

A Civil Aviation Department official said that 40 flights were scheduled to fly in and out of U-Tapao airport yesterday, and Narongsak Sangapong, the acting Thai Airlines president, estimated that it would take four to five days to send the 6,000 tourists home.

A PAD representative said that there were plans to besiege U-Tapao, 90 miles east of Bangkok, as they had Suvarnabhumi and Don Muang airports, but late last night there was no sign of making good on the threat.

PAD protesters – who want to curtail democracy – have been holding demonstrations for the past six months in an attempt to unseat the elected Government of Somchai Wongsawat, the Prime Minister.

On Tuesday they took over Suvarnabhumi airport in Bangkok, but with the Army refusing to move against the protesters and the police dithering, Mr Somchai dismissed General Patcharawat Wongsuwanbut, the police chief.

Officers on the scene showed signs of losing their patience. “All protesters must . . . leave the rally site otherwise law enforcement officers will carry out appropriate and necessary measures to solve the situation,” a police officer said, speaking through a megaphone.

Last night the demonstrators were still at Suvarnabhumi airport, eating disposable packages of food and listening to speeches. The airport blockade threatens Thailand’s economy, which relies heavily on tourism worth an estimated £10.4 billion a year. The Prime Minister has come under extreme pressure to solve the crisis, but although he declared a limited state of emergency, by late last night the police had yet to beginning clearing the protesters from the airport.

The army made it clear that it would not forcibly remove the protesters, while the police have been unwilling to act after their attempt to break up a PAD rally in October left two protesters dead and hundreds wounded. Speaking of the riot police outside the terminal, Ra Werachon, a PAD supporter, cautioned: “If they come here and shoot us, and throw bombs at us, they will lose everything.” Many PAD supporters hope that government-sanctioned violence might push the army into launching a coup.

General Anupong Paochinda, the army chief, has repeatedly denied that he plans a military takeover. Earlier in the week Mr Somchai ignored General Anupong’s demand that he should dissolve the Government and call snap elections.

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