Nov. 26 (Bloomberg) -- Four anti-government protesters were injured in an explosion outside Bangkok’s international airport after demonstrators occupied its main terminal, seeking to topple the government for the second time since a 2006 coup.

“The airport is just a scene of chaos,” said John Watson, chief executive officer of Diethelm Travel Group in Bangkok, Thailand’s biggest inbound tour operator. “Communication has basically broken down. Passengers are feeling very intimidated seeing people walking by with masks, knives, wooden clubs and iron bars.”

About 3,000 tourists were evacuated this afternoon to nearby hotels, said Serirat Prasutanond, general manager at Suvarnabhumi Airport. Cathay Pacific Airways Ltd., Singapore Airlines Ltd. and at least three other carriers canceled Bangkok flights after protesters seized the terminal last night.

“We are focusing upon how we can help the tourists who want to go home,” said Tharit Charungvat, spokesman for Thailand’s Foreign Ministry. “The police can ask for help from military personnel to reinforce officers on the ground. They are discussing the matter.”

The People’s Alliance for Democracy, which helped trigger the coup against former premier Thaksin Shinawatra, wants to force the resignation of Prime Minister Somchai Wongsawat, set to return today from the Asia-Pacific Economic Cooperation forum in Peru. He has rejected the calls and Finance Minister Suchart Thadathamrongvej said today the turmoil will hurt the country’s tourism, trade and investment.

Police Restraint

“Nobody seems to be coming to the government’s defense,” said Michael Montesano, a visiting research fellow at the Institute of Southeast Asian Studies in Singapore. The disorder may lessen support for the protesters and make it easier for the army and police to deploy, he said.

Today’s blast injured four PAD supporters on an access road leading to Suvarnabhumi International Airport at around 6 a.m. this morning, Somchai Sopacharoen, the police chief in the district where the airport is located, said by telephone. Police have avoided using force since an Oct. 7 clash in which two people died and 470 were injured.

The SET Index of stocks dropped 1.7 percent as of 3 p.m. in Bangkok. The measure, which has sunk 56 percent since the protests first erupted in May, is on course for its worst annual performance since the 1997 Asian financial crisis. The baht slid 0.3 percent to its lowest against the dollar in 21 months.

Army Press Conference

Thailand’s military won’t decide whether to send troops to the airport until after a meeting between the army, security officers, government agencies and business representatives this afternoon today, Sirichan Ngathong, an army spokeswoman, said. Army chief Anupong Paojinda will hold a press conference after the meeting, Sirichan said. Military leaders reiterated their commitment not to stage another coup, she said yesterday.

The Bangkok-based PAD, which includes many middle-class Thais and receives support from the country’s royalist elite, accuses Somchai’s ruling party of buying votes to win elections and of trying to protect Thaksin, who fled the country to escape corruption charges.

Thousands of PAD activists, who have occupied Somchai’s official Government House compound in central Bangkok for three months, yesterday stormed his temporary office after forcing parliament to abandon its sessions a day earlier. That postponement may affect Thailand’s ability to sign international trade agreements at a summit of the Association of South East Asian Nations it is hosting Dec. 15-18.

Travel Warning

Singapore’s Foreign Ministry warned its citizens to avoid traveling to Bangkok and postpone their trips. Countries including Singapore and South Korea in September warned travelers about visiting Thailand after protesters forced the closure of its second-busiest airport in the resort of Phuket.

At least five people have died since August as a result of the protests. Two people were hurt yesterday when shots were fired during a clash between protesters and pro-government supporters on a Bangkok highway, Agence France-Presse reported, citing police.

Southeast Asia’s fourth-busiest airport, which last year processed more than 41 million passengers, won’t reopen until at least 6 p.m. local time, said Puttawan Noirod, a spokeswoman for Aeronautical Radio of Thailand. Protesters sought to enter the airport’s control tower, which has been unmanned since the closure, said Somchai Thean-Anant, president of Aeronautical Radio.

Standstill

The terminal has been closed to all flights since 4 a.m. today and it won’t reopen “until the situation returns to normal,” said Serirat, the airport’s general manager.

About 292 flights can’t get in or out of the airport because of the closure, and the airport will lose 53 million baht ($1.5 million) a day in landing fees, he said. The airport typically handles as many as 120,000 people a day, according to Serirat.

Traffic was brought to a standstill on the six-lane road leading to the airport. Cars turned around to drive back with their hazard lights on.

“I’m very angry,” said Aly Mdouj, 36, a South African businessman, as he lay on his luggage inside the main terminal. “This is unbelievable. I need to get home.”

To contact the reporter on this story: Rattaphol Onsanit in Bangkok at ronsanit@bloomberg.net

Last Updated: November 26, 2008 03:18 EST