A Thai protester was killed and four wounded, an emergency official said on Saturday, after an unidentified gunman opened fire on demonstrators whose efforts to topple Prime Minister Yingluck Shinawatra flared into violence over the past two days.
The shooting came 48 hours after clashes between police about 500 protesters, who are determined to disrupt a snap Feb. 2 election called by Yingluck, outside a voting registration centre in which two people were killed and scores wounded.
Petphong Kamjonkitkarn, director of the Erawan Emergency Centre in the Thai capital Bangkok, told Reuters one man in his 30s had been killed and four others suffered gunshot wounds.
The protesters have been rallying for weeks in their attempt to topple Yingluck, who they see as a puppet of her brother and former premier, billionaire tycoon Thaksin Shinawatra, and have vowed to disrupt the election.
Yingluck, who draws her support from the populous voter base among the rural poor in the north and northeast, is determined to go ahead with the poll.
On Friday, her government asked the military for help to provide security for both candidates and voters. However, the chief of the heavily politicised military refused to rule out military intervention, responding that "the door was neither open nor closed" when asked if a coup was possible.
Several hundred protesters are camped out in tents around the walls of Government House in Bangkok. Witnesses said they were sleeping when gunfire suddenly rang out at about 3.30 am on Saturday.
"I was sleeping and then I heard several gunshots. I was surprised," said one 18-year-old protester, who would not identify himself other than by his nickname "Boy".
Other witness said the shots could have come from a car as it drove past the protest site. Reuters television pictures showed bullet holes in a concrete wall and a generator, as well as bloodstains inside in one of the many flimsy tents set up by protesters around Government House.
Protesters showed several small-calibre slugs they had found. Registration for the election was to continue on Saturday, although Thailand's Election Commission has requested that the poll be delayed after Thursday's violence until "mutual consent" from all sides was achieved - an increasingly unlikely outcome.
With the street protests escalating, any delay to a poll that Yingluck's Puea Thai Party would otherwise be expected to win would leave her government open to legal challenges or, worse still, military or judicial intervention.
Thailand's military has staged or attempted 18 coups in 81 years of democracy, making Friday's comments by General Prayuth Chan-ocha more chilling for Yingluck and Thaksin, who was toppled in a 2006 coup.
The protesters draw strength from Bangkok's conservative middle classes and elite, many with ties to the judiciary and military, who resent the rise of the billionaire Shinawatra family and their political juggernaut.
They accuse them of manipulating Thailand's fragile democracy by effectively buying the support of the rural poor with populist policies such as cheap healthcare, easy credit and subsidies for rice farmers. Instead of an election, the protesters want an appointed "people's council" to oversee reforms before any future vote.
The first two years of Yingluck's government had been relatively smooth until a blunder by Puea Thai in November, when it tried to push through an unpopular amnesty bill that would have exonerated Thaksin from a 2008 graft conviction he says was politically motivated. Thaksin fled into exile to avoid jail.