Five flights yesterday ferried home about 1,400 Chinese tourists stranded in Thailand, where tension grew with thousands of government supporters clashing with anti-government protesters in Bangkok.

According to the Ministry of Foreign Affairs, more than 1,000 Chinese are still stuck in Thailand. Four more planes were scheduled to bring some of them back last night but it was not clear how many would be on board.

A spokeswoman for the Civil Aviation Administration of China (CAAC) said it is "one of the biggest efforts" made in chartering flights to bring back Chinese stranded overseas.

She said the military airport that Thailand opened as a temporary international airport is in chaos.

"The airport has only one runway, two security check channels and a waiting room of less than 200 sq m, but thousands of people flooded in," E Wenxin, an Air China manager stationed in Thailand, said.

"We have to maintain order, and fight for everything from refueling to the runway," he said.

In Thailand, thousands of pro-government supporters also rallied in Bangkok in their first significant show of strength since the People's Alliance for Democracy (PAD) launched its "final battle" last Monday to unseat the government.

By early evening at least 20,000 of the government supporters had gathered, most wearing red that is associated with their cause. They carried Thai flags, red flags and red heart signs with former Thai prime minister Thaksin Shinawatra's picture.

Early yesterday morning, an explosion in the Thai prime minister's office compound injured about 45 people. The blast at the Government House, which has been occupied by thousands of anti-government protesters since August, occurred during a rally by supporters of the PAD, officials said.

Flights in and out of Suvarnabhumi international airport and the mostly-domestic Don Muang airport have been paralyzed since late Tuesday and Thursday respectively by the PAD siege.

The airport blockades are the latest escalation in the PAD's battle to unseat Prime Minister Somchai Wongsawat, who they accuse of being a front for former leader Thaksin, Somchai's brother-in-law, who was ousted in a military coup in 2006 and lives in exile.