A gunman opened fire at opposition protesters in the Thai capital on Saturday, killing one person and wounding several others, as demonstrators sought to disrupt candidate registrations ahead of February elections.
The shooting fanned tensions in the politically divided kingdom, coming after weeks of mass street protests seeking to oust Prime Minister Yingluck Shinawatra and curb her billionaire family's political dominance.
Yingluck has called elections for Feb. 2 in the hope of bringing an end to the rallies, which have drawn tens of thousands of people calling on her to step down.
But the protesters have vowed to block the vote, saying it will only return the Shinawatra clan to power.
The pre-dawn shooting by at least one unidentified gunman targeted a group of demonstrators camped overnight near Government House in the Thai capital, police said. Armed provocateurs have a history of trying to stir tensions in the politically polarised kingdom.
"There is an attempt to incite violence and hatred between protesters and the police," said a spokesman for the anti-government movement, Akanat Promphan.
Anti-government demonstrators besieged a number of candidate registration venues in Thailand's opposition-dominated south on Saturday, forcing officials to suspend the process in seven provinces.
By the end of the day 377 candidates had registered in 343 constituencies, while 32 constituencies still had no candidates, an election commission official told AFP.
A first round of registrations for party-list candidates was completed on Friday after several tense days during which protesters tried to block the process.
Thailand has been periodically convulsed by political bloodshed since Yingluck's older brother Thaksin Shinawatra was overthrown by royalist generals in a coup seven years ago.
The protesters, a mix of southerners, middle class Thais and urban elite, accuse the billionaire tycoon-turned-politician of corruption and say he controls his sister's government from his self-exile in Dubai.
They want an unelected "people's council" to run the country to oversee loosely-defined reforms — such as an end to alleged "vote buying" — before new elections are held in around a year to 18 months.
Yingluck's government still enjoys strong support in the northern half of the country and is expected to win the election if it goes ahead.
The country's Election Commission on Thursday urged the government to postpone the February polls after protesters stormed a party registration venue in Bangkok, triggering clashes in which a policeman and a demonstrator were shot dead by unidentified gunmen.
But the government rejected the plea, saying that a delay would only bring more violence.
It has appealed to the military to provide security for election candidates and voters following several outbreaks of street violence in recent weeks, in which eight people have been killed and about 400 wounded.
The army chief insisted Friday that the military would remain neutral and said it was up to the election authorities whether the vote could go ahead, but he did not rule out another coup.
"The door is neither closed nor open. In every situation, anything can happen," Gen. Prayut Chan-O-Cha said when asked about the possibility of a coup, without elaborating.
Thaksin's "Red Shirt" supporters have accused the demonstrators of trying to incite the military to seize power again, in a country with a history of intervention by the military and the courts to remove elected governments.
Red Shirt leader Nattawut Saikuar warned Prayut Saturday that the movement would not tolerate another coup.
"We have to shut all doors to a coup and not allow them to re-open otherwise all democracy-loving people will rise up against you," he said at a news conference.
It is the worst civil strife since 2010, when more than 90 people were killed in a bloody military crackdown on pro-Thaksin Red Shirt protests under the previous government.