Thai anti-coup protesters briefly scuffled with soldiers after a woman blew a plastic whistle and hurled insults, Reuters reported.
The number of people wounded in a firearm attack on Thai protesters has been updated to four, after an unidentified gunman opened fire on anti-government demonstrators.
One person was killed in the attack upon the protesters whose efforts to topple Prime Minister Yingluck Shinawatra have flared into violence in recent days.
An anti-government protester has been killed and two injured in a gun attack in the Thai capital Bangkok, according to the Associated Press.
The incident early today close to a protest site will hasten fears that the country's political crisis could lead to a serious outbreak of violence.
The Erawan medical centre said a 31-year man was killed with wounds to his torso.
Protesters are seeking to topple prime minister Yingluck Shinawatra ahead of elections scheduled for February 2.
Thailand's government has rejected calls to postpone the election and said the February 2 poll "will go ahead", Reuters reports citing the deputy Prime Minister.
The decision to not postpone the election comes on a day when a police officer was killed after clashing with anti-government protesters in the country's capital, Bangkok.
Thai police have fired teargas and rubber bullets at anti-government protesters in the capital Bangkok after demonstrators tried to disrupt planning for a February election.
A police officer has been shot dead in Bangkok, Thailand, during clashes between security forces and anti-government protesters, AFP reports.
Jongjet Aoajenpong, director of the Police General Hospital where the officer was taken for treatment told the news agency: "He was shot in his chest and brought to hospital by helicopter.
"A team of doctors tried to resuscitate him for more than half an hour."
Violence broke out after protesters tried to force their way into a sports stadium in the capital, where representatives from around 30 political parties were gathered to register for February elections.
Tens of thousands of anti-government protesters have gathered outside Government House in Bangkok calling for Prime Minister Yingluck Shinawatra and her administration to resign.
Some protesters climbed the fences but the gathering appeared to be mostly peaceful.
Yingluck said on Saturday the police would act with restraint if people tried to occupy public buildings, including their main target, her Government House offices.
Street battles between protesters and police which started over the weekend in the Thai capital of Bangkok have intensified today.
The violence took place around key institutions - including the Parliament building and police headquarters - with officers using rubber bullets, water cannon and tear gas against the protesters.
Protest leaders are calling for a "people's council" to be set up to run the country, but Prime Minister Yingluck Shinawatra said today that such a move would be undemocratic.
Footage taken by a drone and posted on social media shows aerial views of the violent clashes between police and anti-government protesters in Bangkok yesterday.
Thai police are seen using water cannon and tear gas in an attempt to disperse the crowds, who are attempting to launch a "people's coup" on the government.
At least two people have died as a result of the violence.
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The Foreign and Commonwealth Office has advised Britons to "avoid all protests, political gatherings and demonstrations", following violent protests in the Bang Kapi district of Bangkok.
Several people have reportedly been killed during street clashes as 30,000 protesters launched a "people's coup" on the Thai government.