BANGKOK » Anti-government protests in the Thai capital turned violent today and at least one man was killed and five wounded by gunshots, police said.

It was not immediately known who fired the shots or what side the victims were on. National Police Deputy Spokesman Anucha Romyanant said the dead man was a 21-year-old male with two bullet wounds.

The shooting Saturday night occurred after scattered violence during the day involving government opponents waylaying and beating several people they believed were going to a rally at a stadium of "Red Shirt" government supporters.

The anti-government demonstrators are seeking to topple Prime Minister Yingluck Shinawatra’s government, which they believe serves the interests of her brother, former Prime Minister Thaksin Shinawatra who was ousted by a 2006 military coup after being accused of corruption and abuse of power.

Scattered violence had occurred during the day involving government opponents waylaying and beating several people they believed were going to a rally at a stadium of "Red Shirt" government supporters.

The protesters have for the past week occupied or besieged government offices in what they describe as a civil disobedience campaign. They have vowed to seize the prime minister’s offices on Sunday.

During the day, a mob of anti-government protesters had attacked at least two people they suspected of supporting the current Thai government, smashed the windows of a moving Bangkok bus and the windshield of a taxi carrying people wearing red shirts, a sign of government support.

The mob, drawn from more than 1,000 protesters led by university students who oppose the government, tried to block people from entering a stadium where Yingluck’s supporters were holding a rally.

The national police gave televised reaction immediately, highlighting the fears of an escalation.

"The situation has almost returned to normal. About 100 police officers are taking care of the situation," police spokesman Maj. Gen. Piya Uthayo said before the nighttime clashes.

The week of dramatic protests against Yingluck’s government has included seizing the Finance Ministry, turning off power at police headquarters and camping at a sprawling government office complex.

Protesters vowed to turn up the pressure Sunday by seizing more government ministries and key offices, including the Government House, which is the prime minister’s office compound.

Saturday’s violence was isolated to the area around the stadium, but it was bound to increase tension and raise concerns of new political turmoil and instability in Thailand.

The crowd first attacked two men, one of whom was pulled off the back of a motorcycle and punched and kicked. Both men were seen being pulled away by security and treated for head injuries.

The taxi that was attacked managed to move away. Police then moved in, and the students began to retreat to their nearby university but then spotted a bus carrying some passengers wearing red shirts and chased after it.

The students threw stones at the bus and then began hitting it on all sides with sticks, shattering or breaking the buses windows as terrified passengers inside dropped to the floor. It was not immediately clear if anyone on the bus was injured before it moved away.

Protest leaders backed by the opposition say they want to uproot the political machine of former Prime Minister Thaksin Shinawatra, Yingluck’s brother, who was ousted by a military coup in 2006 for alleged corruption and abuse of power.

The protesters accuse Yingluck of being a puppet of her billionaire brother.

Thaksin, who lives in Dubai to avoid a two-year jail term for a corruption conviction he says was politically motivated, is a highly polarizing figure in Thailand. An ill-advised bid by Yingluck’s ruling Pheu Thai party to push an amnesty law through Parliament that would have allowed his return sparked the latest wave of protests.

Associated Press writers Grant Peck, Jocelyn Gecker and Raul Gallego Abellan contributed to this report.