Hundreds of Thai riot police have fled their checkpoint near Bangkok's besieged airport after they were attacked by protesters.

An estimated 3,000 people, including hundreds of Britons, are stuck in Thailand after flights in and out of Suvarnabhumi International Airport were cancelled when the anti-government People's Alliance for Democracy took over the building.

PAD members - who are demanding the resignation of Thai Prime Minister Somchai Wongsawat - threw firecrackers and iron rods at police manning the checkpoint on the expressway leading to the airport, witnesses said.

Elsewhere, around 34 protesters were injured when a grenade was thrown at Government House in Bangkok - which PAD members have been occupying since August.

Meanwhile, the plight of the trapped Britons has been described as "deeply concerning" by a Foreign Officer minister.

They include the family of England rugby league captain Jamie Peacock, 30, who plays for Leeds Rhinos. His wife Faye, 33, who is six months pregnant, their son Lewis, four, and Faye's mother Pat, were due to fly back to England from Bangkok on Monday.

They had been supporting Peacock at the Rugby League World Cup when their flight was cancelled.

He does not believe enough is being done to help those stranded and said: "I think the story has gone under a little bit, and more of an effort needs to be made to get all the people who are stuck there out of there, because the country is on the brink of a lot of trouble."

Meanwhile, Foreign Office Minister Bill Rammell said: "The situation facing the many British nationals stranded in Bangkok is frustrating and deeply concerning.

"Our consular teams on the ground and in London are doing all they can to help. They are taking numerous calls and are meeting as many British nationals as possible."

A day after their police chief was sacked for mishandling the protests, commanders on the ground said they would not yet forcibly evict the protesters.

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