Anti-government protestors have forced the closure of Bangkok’s second airport, a major domestic hub.
It comes a day after Thailand’s main international terminal was taken over by opposition supporters calling for the government to step down.
Demonstrators moved in in what observers say seems to have been an attempt to stop officials flying to Northern Thailand to meet up with Prime Minister Somchai Wongsawat.
Somchai is in the northern town of Chiang Mai after the plane bringing him back from the APEC summit in Peru was forced to divert due to the unrest in Bangkok.
He has rejected a call for fresh elections from the head of the Thai Army, saying his administration is legitimate and he will continue to govern.
A rival pro-government group has threatened retaliation on the streets but witnesses say Bangkok appears calm.
The authorities have ordered the protestors to leave the main airport but they have refused.
All flights have been cancelled and thousands of travellers remain stranded at the terminal.