By Ed Cropley
BANGKOK, Nov 29 (Reuters) - Hundreds of anti-government protesters forced several dozen Thai riot police to abandon a checkpoint on Saturday as they tightened their siege of the country's main airport, witnesses said.
Around 2,000 People's Alliance for Democracy (PAD) supporters forced back about 150 police from a kilometre (0.6 mile) north of Suvarnabhumi Airport, although the incident passed off without violence.
The protesters are seeking to oust Thai Prime Minister Somchai Wongsawat in the latest escalation in a long-running political crisis.
A day after their police chief was sacked for mishandling the protests, commanders on the ground said they would not yet try to evict by force the thousands of protesters at Suvarnabhumi and Don Muang airports.
But PAD supporters were taking no chances and on Saturday deflated the tyres of ambulances and police vehicles at the police checkpoint. Several vehicles were left stranded in the middle of the road.
The PAD say they are ready for a prolonged siege, with their "security guards" armed with clubs, sticks and golf clubs, and dug in behind a series of barricades of fire trucks, razor wire, car tyres and luggage trolleys.
PAD co-leader and retired general Chamlong Srimuang told supporters on Saturday not to go to Suvarnabhumi as there were enough people there and instead go to Government House, where the protests started months ago. "Too many people will not help if police shut us there. If you're on your way here, please go to the Government House because if police shut us here, we'll still have people to help," he said.
Chamlong said PAD leaders had not yet held any talks with authorities.
"We are still open to talks but only with people directly involved in the situation such as Somchai," he told a news conference.
"They can talk with any of our leaders and wherever, but nobody contacts us yet.
He also offered some hope of a way out, without giving details.
"We believe the situation will not be prolonged as we always think of the important day. But we believe it will be eased before Dec. 5," he told a news conference, refering to revered King Bhumibol Adulyadej's birthday.
In a televised address on Thursday night, Prime Minister Somchai said the PAD members barricaded at the airports were doing massive damage to the economy, but he would avoid violence to end the protests.
Pressure is building on the army to oust the prime minister, as they did Thaksin in 2006, after Somchai rejected military calls to quit this week.
But army chief Anupong Paochinda has said he would not take over, arguing the military cannot heal fundamental political rifts between the Bangkok elite and middle classes, who despise Thaksin, and the poor rural and urban majority who love him.
Exporters were scrambling to get perishable goods and key components to customers around the world.
The question of compensation may arise later, but for now, they are focused on shipping goods, said Kasem Jariyawong, president of the Thai Air Freight Forwarders Association.
A prolonged closure of Suvarnabhumi, which can handle 3 million tonnes of cargo a year, would do serious damage to an export-driven economy already struggling to cope with a global slowdown, experts say.
Repairing Thailand's tarnished image as a safe place to do business and travel may also take time.
The government began shuttling thousands of stranded tourists by bus to U-Tapao, a Vietnam War-era naval airbase 150 km (90 miles) east of Bangkok, as an alternative landing site for airlines, but travellers reported delays and confusion. (Writing by David Fox; Editing by Alex Richardson)