Thai troops fired at protesters on Saturday in a third day of fighting on Bangkok's streets that has killed 17 people as soldiers struggle to isolate a sprawling encampment of demonstrators seeking to topple the government.
Soldiers crouched behind sandbags or atop buildings fired live rounds at protesters armed with petrol bombs, guns and homemade rockets in clashes around the business district. One was shot in the chest while trying to ignite a tire.
At Din Daeng intersection, north of the protest site, three bodies were evacuated on stretchers, a Reuters witness said. Two suffered head wounds. Troops also swarmed into a parking lot at the popular Dusit Thani hotel outside the protest site.
Protesters set fire to vehicles, including an army truck.
That followed a long night of thundering grenade explosions and sporadic gunfire as the army battled to set up a perimeter around a 3.5 sq-km (1.2 sq-mile) protest site of red-shirted demonstrators who refuse to leave.
"We'll keep on fighting," said Kwanchai Praipana, a leader of the red-shirted protesters, calling on Prime Minister Abhisit Vejjajiva to resign and take responsibility for Thailand's deadliest political crisis in 18 years.
He said supplies of food, water and fuel were starting to run thin but they had enough to last "days."
The crisis has paralyzed parts of Bangkok, squeezed Southeast Asia's second-biggest economy and scared off tourists.
United Nations Secretary-General Ban Ki-Moon expressed concern over "the rapidly mounting tensions and violence."
"He strongly encourages them to urgently return to dialogue in order to de-escalate the situation and resolve matters peacefully," his spokesman said in a statement.
The Canadian government urged both sides to return to talks after a Bangkok-based Canadian journalist was shot three times, one of three journalists wounded in fighting that has spiraled into chaotic urban warfare where front lines shift quickly.
By Saturday, troops had taken control of checkpoints on at least three roads surrounding the main protest site, checking identification cards in an attempt to stop people from joining thousands in the area, including women and children.
The government said on Friday it would restore order "in the next few days" as the city of 15 million people braced for a crackdown to end a six-week protest by thousands of "red shirts" packed into an area of high-end department stores, luxury hotels, embassies and expensive residential apartments.
The Erawan Medical Center in Bangkok said 16 people had been killed in the latest fighting.
"It's unlikely to end quickly," said a source close to army chief Anupong Paochinda, fearing more protesters would arrive to surround and attack soldiers.
"There will be several skirmishes in the coming days but we are still confident we will get the numbers down and seal the area," added the source, who declined to be identified by name.
The number of protesters in the main encampment appeared to have dropped overnight but several thousands remained, many singing and listening to speeches by protest leaders. Some leaders, including the movement's chairman, have disappeared.
Protesters are barricaded behind walls of kerosene-soaked tires, sharpened bamboo staves, concrete blocks and razor wire.
Before fighting began on Thursday with the shooting of a renegade general allied with the protesters, the two-month crisis had already killed 29 people and wounded about 1,400 - most of whom died during an April 10 gun battle in Bangkok's old quarter.
The fighting is the latest flare-up in a polarizing five-year crisis between a royalist urban elite establishment, who back the prime minister, and the rural and urban poor who accuse conservative elites and the military's top brass of colluding to bring down two elected governments.
Those governments were led or backed by exiled former premier Thaksin Shinawatra, a graft-convicted populist billionaire ousted in a 2006 coup who is a figurehead of the protest movement.
The red shirts and their supporters say the politically powerful military influenced a 2008 parliamentary vote, which took place after a pro-Thaksin party was dissolved, to ensure the British-born, Oxford-educated Abhisit rose to power.
Five-year Thai credit default swaps, used to hedge against debt default, widened by more than 30 basis points on Friday - the biggest jump in 15 months - to 142 basis points
"With gun battles and grenades going off, investors will look elsewhere," said Danny Richards, an analyst at the Economist Intelligence Unit.
"I don't think many see the end of this protest as the end of the crisis. When there's an election, either side will reject the legitimacy of the other and we'll be back to square one."
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