Anti-government protesters surrounded Thailand's parliament on Wednesday, causing the session to be halted early after many lawmakers fled the building, according to officials.
About 5,000 red-shirted demonstrators, many of whom support fugitive former premier Thaksin Shinawatra, massed outside parliament's gates as part of rolling rallies aimed at forcing immediate elections, AFP reports.
Parliament president Chai Chidchob declared the lower house meeting closed just after 11am local time due to the low number of lawmakers present.
Prime Minister Abhisit Vejjajiva had already left the building after attending a cabinet meeting, officials said.
The cabinet extended a tough security law on Wednesday as protesters refused to leave Bangkok's main commercial district for a fifth day and vowed to march to the prime minister's house.
The demonstrators are mostly from Thailand's poor and working class and see Mr Abhisit's government as elitist and undemocratic.
Government spokesman Supachai Jaisamut said the authorities were ready to use emergency law if needed.