by Anusak Konglang

BANGKOK, Sept 2, 2008 (AFP) - Thousands of pro- and anti-government protesters clashed violently in the Thai capital early Tuesday, leaving dozens wounded and one person reported dead, officials said.

Thailand's police chief said he had called in army reinforcements to help quell the unrest, which occurred when groups of protesters calling for the prime minister's resignation clashed with government supporters.

"Initial reports which need to be confirmed later are that one died and 38 were injured," said Peeratong Saichoew, a doctor with the Bangkok administration's media reporting bureau.

"There is a report that one person was injured from gunshots while the rest injured from fighting. Now they are being treated at six hospitals nearby."

Thai television showed men wearing helmets and carrying batons and people bleeding in the street, and national police chief Patcharavat Wongsuwan told a local news channel the army had been called in to help calm the situation.

"The number of police is still enough to take care of the situation but we have asked the assistance from the army to help," he said.

The violence took place not far from the site where about 15,000 demonstrators have been besieging Government House for a week, demanding that Prime Minister Samak Sundaravej step down.

The activists accuse Samak of acting as a puppet for ousted prime minister Thaksin Shinawatra, who now lives in exile in Britain after the same protest group helped topple his government in 2006.

Meanwhile, Thailand's biggest union Monday called for a strike to support the anti-government protesters.

The 200,000-strong State Enterprises Workers' Relations Confederation said it would cut power and water supplies to government agencies "to put pressure on the government to quit and stop damaging our country."

The confederation's members have never taken strike action en masse, despite threats from their leadership.

One top government official accused the protesters of "guerrilla warfare," urging the workers not to join the protests that have already won support from railway crews who have crippled national train services since Thursday.

"We think that their strategy is guerrilla warfare," the official told reporters, speaking on condition of anonymity.

Tuesday's violence was the worst since the start of the campaign to oust Samak, although protesters clashed with riot police on Friday, causing minor injuries.

The anti-government activists have also taken their campaign to the provinces, closing key regional airports for two days, including the nation's second-busiest hub on the resort isle of Phuket.

Samak called an emergency session of parliament on Sunday, but the debate failed to produce any plan for ending the protests and the premier angrily rejected calls to dissolve parliament and hold new elections.

"Why are the only solutions house dissolution and resignation? Why can't we choose the third option, which is to show the world that we maintain our democracy," he said.

The leaders of the so-called People's Alliance for Democracy (PAD) have already said that they would not accept a parliamentary solution to the crisis.

In addition to demanding that Samak resign, they want an overhaul of Thailand's system of government, saying only 30 percent of seats in parliament should be elected, with the rest appointed.

PAD gathers most of its support from Bangkok's traditional elite and a portion of the middle class. Its leaders openly disparage the merit of votes cast by the nation's rural poor, who have thrown their support behind Thaksin and now Samak.

Thaksin was toppled by royalist generals in a military coup in 2006, and is now living in exile in Britain to avoid corruption charges at home.

But his allies still fill many top seats in government, and Samak won elections in December by campaigning as Thaksin's proxy.