Two policeman were killed and at least seven were wounded in gun and grenade attacks in the Thai capital overnight.
Police said Saturday a drive-by shooting and a series of explosions shook central Bangkok near the center of a standoff between anti-government Red Shirt demonstrators and security forces. It is not clear who was behind the violence.
Protest leaders were quick to condemn the violence and denied any involvement in the attacks.
The new violence comes as protesters and government officials haggle over the terms of a reconciliation plan that could end the demonstrators' two-month long standoff.
Since the protests began in March, at least 29 people have been killed in fighting between the demonstrators and security forces.
On Thursday, Thai Prime Minister Abhisit Vejjajiva warned opposition protesters he will not proceed with an offer to hold early elections unless they end their occupation of Bangkok's commercial center.
Mr. Abhisit said that if the protesters do not go home, he will not dissolve parliament as part of a reconciliation plan that calls for elections on November 14.
The Red Shirts have agreed to the reconciliation plan in principle but say they want clarifications from the government, including more specifics on Mr. Abhisit's election offer.
The protesters are demanding an early election to replace a government they see as elitist and undemocratic. Many of them are rural poor and working class activists who support former prime minister Thaksin Shinawatra, ousted in a 2006 coup for alleged corruption.
Some information for this report was provided by AFP and Reuters.