A Thai anti-government protest leader was shot and killed in Bangkok on Sunday when violence erupted as demonstrators blocked early voting in many areas of the capital ahead of a disputed election next week.
It brought the death toll to 10, with scores wounded, since protesters took to the streets in November, vowing to shut down the capital and force Prime Minister Yingluck Shinawatra from office.
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A spokesman for the national police, Piya Utayo, identified the dead man as Suthin Tharatin, one of the protest leaders. "Suthin was shot in the head and in the chest," he said.
Yingluck called the February 2 election, hoping to cement her hold on power, but the protests have continued and the Election Commission has been pushing to delay the vote.
In a clear setback for Yingluck, a senior government official said that as many as 45 of the 50 polling stations set up in Bangkok for advanced voting had been shut because of anti-government protesters.
Bangkok police said clashes had broken out between anti-government protesters and Yingluck supporters, with the two sides trading punches before shots were fired. The Erawan Medical Center, which monitors Bangkok hospitals, said 11 people were hurt in the clashes in the Bang Na district.
It was not immediately clear who had fired the shots, but the protesters accused the government and police of trying to intimidate them.
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"The government has allowed thugs to use weapons," Akanat Promphan, a spokesman for the protesters, told reporters. Private gun ownership is widespread in the country.
The violence, the worst in a month, came after a state of emergency took effect on Wednesday and adds to doubts over whether the February 2 election can go ahead.
The U.S. State Department said on Sunday it was "deeply troubled by efforts to block polls and otherwise prevent voting in Thailand, and by the most recent acts of political violence.
"While we do not take sides in the political dispute and strongly support freedom of expression and the right to peaceful protest, preventing citizens from voting violates their universal rights and is inconsistent with democratic values," State Department spokeswoman Jen Psaki said in a statement.
Chris Baker, a historian and Bangkok-based analyst, said the violence added pressure on Yingluck to delay the vote.
"It does weaken the government's position. The protesters will blame this on the government," said Baker. "With or without this incident, the likelihood for violence was there already. I don't think it changes in the trajectory."
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The protests are the latest eruption in a political conflict that has gripped Thailand for eight years and is starting to hurt growth and investor confidence in Southeast Asia's second-largest economy.
The conflict broadly pits Bangkok's middle class and elite, and followers in the south, against mainly poor rural backers of Yingluck and her brother, ousted former Premier Thaksin Shinawatra, in the populous north and northeast.
The protests mark the biggest demonstrations since deadly political unrest in April and May 2010, when Thaksin's "red-shirt" supporters paralyzed Bangkok to remove a government led by the Democrat Party, now in opposition. More than 90 people were killed and more than 2,000 injured in that unrest.
Yingluck, who would probably win the election easily, is set to meet Election Commission officials on Tuesday. The Democrat Party also plans to boycott the election.
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The protesters, led by firebrand former Premier Suthep Thaugsuban, accuse Yingluck of being Thaksin's puppet and want an unelected 'people's council" to oversee reform before any future election is held.
On Saturday, a government minister said Yingluck was prepared to discuss cancelling the February 2 election if the activists ended their protests.
Foreign Minister Surapong Tovichakchaikul, also a deputy prime minister, said in a televised address the blocking of advance voting was "a serious offence" and that protesters had used force to prevent people voting.
Yingluck's government had already warned that anyone who tried to stop voting would be jailed or fined.
City officials said they had begun negotiating with the protesters. "We have to negotiate with them and let them know that blocking the election is illegal," said Luckana Rojjanawong, a Bangkok district official said.
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The election was already in doubt after a Constitutional Court ruling on Friday that opened the possibility of a delay. The Election Commission is seeking the delay, arguing that the current environment is too unsettled.
The protesters say Thaksin's powerful political machine has subverted Thailand's fragile democracy by effectively buying the support of rural voters with populist policies such as cheap healthcare and subsidies for rice farmers.
Paul Chambers, director of research at the Institute of South East Asian Affairs in northern Chiang Mai, said before the violence began that the disruption of advance polling would add impetus to the calls for an election delay.
"The ability of those against advance voting to keep it from happening today could signal what may come next week - a decision to delay the vote due to an inability to hold the election properly," Chambers said.
About 49 million voters out of Thailand's population of 66 million are eligible to cast ballots, with about 2.16 million registered for early polling.
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Yingluck's government had been proceeding relatively smoothly until her Puea Thai Party miscalculated in November and tried to force through an amnesty bill that would have allowed her brother to return a free man despite a 2008 graft conviction he says was politically motivated.
Thaksin, a billionaire former telecoms tycoon, was ousted by the military in 2006.