From CNN.com:

BANGKOK, Thailand (CNN) -- Thousands of anti-government protesters partially shut down Bangkok International airport Tuesday.

All departing flights were canceled after the protesters broke into the passenger terminal, Serirat Prasutanond, the director of Suvarnabhumi airport, said. There are also demonstrators sitting on the road in front of the terminal, video of the protest showed.

The demonstrators are trying to prevent Thai Prime Minister Somchai Wongsawat from returning to the country following an international summit in Peru.