Political violence shakes Thai capital

One protester has been killed after an attack on a bus carrying government's supporters in Bangkok.

Thai police have fired tear gas and a water cannon at protesters trying to storm the government headquarters to overthrow Prime Minister Yingluck Shinawatra, after violence in the capital left three dead and dozens wounded.

The bloodshed on Saturday is the latest in a series of outbreaks of civil strife in the kingdom since royalist generals ousted billionaire tycoon-turned-premier Thaksin Shinawatra, Yingluck's brother, seven years ago.

The street rallies, aimed at replacing Yingluck's government with an unelected "people's council", are the biggest since mass pro-Thaksin protests in Bangkok three years ago left dozens dead in a military crackdown.

Police fired several tear gas cannisters as well as water cannon after protesters tried to breach barricades and cut barbed wire protecting Government House, which was heavily guarded by security forces including unarmed soldiers, according to an AFP reporter.

Yingluck was not present at the time. The government denied rumours that she had fled the country but her whereabouts were unknown. Tear gas was also fired at protesters near the metropolitan police headquarters several kilometres away.

Demonstrators also marched on major television stations while several large shopping malls, including one that was set ablaze during political unrest in 2010, were closed as a precaution.

Violence broke out late Saturday in the area around a suburban stadium where tens of thousands of pro-government "Red Shirts" had gathered in support of Yingluck, who has faced weeks of street protests.

One student and two Red Shirt supporters were killed, deputy national police chief Worapong Siewpreecha told AFP. More than 50 people were wounded.

The dead and injured suffered a range of wounds including gunshots and stabbings. The circumstances were unclear but the violence came after an anti-government mob attacked Red Shirts arriving to join the rally in Ramkhamhaeng district.

They were the first deaths since the mostly peaceful demonstrations began a month ago. Both sides blamed each other for attacking their supporters.

The violence prompted Red Shirt leaders to end their rally, which had drawn tens of thousands of mainly rural poor in support of Yingluck and her brother Thaksin, who lives in self-imposed exile but remains a hugely divisive figure in Thailand.

While the protesters' numbers have fallen sharply since an estimated crowd of up to 180,000 people joined an opposition rally on November 24, they have increasingly sought out high profile targets in what experts believe could be an attempt to provoke a military coup.

The kingdom has seen 18 actual or attempted coups since 1932, most recently with Thaksin's overthrow in 2006, but the military has appeared reluctant to intervene in the current standoff.

In a sign of potential discord between the different branches of the security forces, the army chief urged the police to stop firing gas cannisters.

"I have contacted the national police chief and asked the police to stop firing tear gas," General Prayut Chan-O-Cha told AFP. "Both sides must stop."