Dozens of riot police with truncheons and shields gathered at Bangkok's Suvarnabhumi airport today after talks with anti-government protesters apparently failed to end a crippling blockade.
About 100 police have set up a perimeter at the airport headquarters building, about 300 metres from where the People's Alliance for Democracy (PAD) protesters had besieged the main terminal.
Thai Prime Minister Somchai Wongsawat sacked his national police chief earlier today, fuelling speculation that the government is preparing to crackdown on protesters besieging Bangkok's main airports.
General Patcharawat Wongsuwan, who was moved to an inactive post, had resisted previous orders to crackdown on the street protesters who began a "final battle" to unseat the government on Monday, Thai media reported.
Police said tonight they hoped talks with protest leaders would end the siege, but warned they would "take other steps" if they failed.
"We are asking them to allow the airport to resume operations," Lieutenant-General Suchart Muenkaew, the chief police negotiator, told reporters. "We will keep talking, but if it fails we will take other steps. The last step will be to disperse them."
The siege at Don Muang and Suvarnabhumi International Airport have cut the Thai capital's air links to the world, leaving thousands stranded and hurting the tourist-dependent economy.
A government spokesman said the economy could lose at least 100 billion baht (€2.2 billion) if the sieges drag on for a month, and GDP growth for the year could be cut to 4 per cent from a current estimate of 4.5 per cent, already a seven-year low.
Declaring a state of emergency at the airports from the government stronghold of Chiang Mai, 700 km north of Bangkok, prime minister Somchai Wongsawat said the export- and tourism-driven economy could not tolerate further disruption.
But with security forces reluctant to act, and the protesters insisting they'll stay out until the government falls, the standoff could continue.
PAD guards had set up roadblocks on the main expressway to the airport and were stopping all cars and checking passengers and trunk compartments. The roadblocks were manned by youths in black jackets, faces partly covered by masks. Some wore body armour and wielded wooden stakes and golf clubs.
"We will not leave. We will use human shields against the police if they try to disperse us," PAD leader Suriyasai Katasila said.
Thailand's three-year-old political crisis has deepened dramatically since the PAD began a "final battle" on Monday to unseat a government it accuses of being a pawn of former leader Thaksin Shinawatra, ousted in a 2006 coup. Mr Somchai is Mr Thaksin's brother-in-law.
Pressure has built on the army to step in since Mr Somchai rejected military calls to quit, but pro-government forces threaten to take up arms if the elected administration is ousted, raising fears of major civil unrest.