Thai troops opened fire on protesters for a second consecutive day of fierce clashes in the heart of Bangkok that has left five people dead and at least 46 wounded.

Security forces moved to regain control of a road close to the Suan Lum Night Bazaar, a popular spot with tourists, after Red Shirt protesters spilled out of their fortified rally base which was under siege by troops.

The protesters, who are trying to bring down the government of prime minister Abhisit Vejjajiva, threw stones, used slingshots and launched fireworks at the troops.

Three journalists, one of them a Canadian with the France 24 television channel, were shot in their legs and wounded while covering the violence.

Soldiers used tear gas against the protesters, who set fire to piles of tyres in the road, torched an empty police bus and vandalised army vehicles as well as a water cannon as part of their efforts to disrupt the lockdown.

Volleys of gunfire rang out through the afternoon, sending people fleeing in panic. At one point troops fired directly at protesters and then advanced up a road shooting into the air.

Two of the dead appeared to be Red Shirt security guards, said the director of the hospital where they were taken, adding that one victim was shot in the temple and the other in the chest.

A third fatality was a 32-year-old man who died earlier of gunshot wounds.

Red Shirt leaders have warned the government to prepare for a great, tragic night ahead.

At least 35 people have been killed and about 1,000 injured in Bangkok in a series of confrontations and attacks since the protests began in mid-March.

The mood was tense inside the encampment, which has been fortified with razor wire, truck tyres doused with kerosene and sharpened bamboo poles.

“Abhisit has already started civil war,” top Red Shirt Nattawut Saikuar said.

“We urgently demand the government withdraw the military and stop all violence. I don’t know how we can survive the night if Abhisit does not agree to a ceasefire.”

The Red Shirts consider Mr Abhisit’s government illegitimate because it came to power in a 2008 parliamentary vote after a court ruling ousted elected allies of their hero, former premier Thaksin Shinawatra, who was unseated in a 2006 coup.

Defence minister General Prawit Wongsuwon said the military operation was meant to force the movement’s leaders back to talks with the government.

The army had warned Thursday it would deploy snipers around the protest site and blocked roads to prevent more protesters joining in.

A renegade general allied with the Red Shirts was fighting for his life after being shot late Thursday close to the protest site. His supporters said he was targeted by a sniper. The army denied any involvement in the incident.

Major-General Khattiya Sawasdipol had a “low” chance of survival, said Chaiwan Charoenchokethavee, a hospital director.

Thaksin thwarted

The violence came after Mr Abhisit shelved a plan to hold early elections in November after reconciliation efforts broke down.

Montenegro has banned former Thai premier Thaksin Shinawatra from using his stay in the former Yugoslav republic for political ends, Montenegro’s foreign minister, Milan Rocen, said.

“We warned Mr Shinawatra that, like any other citizen of Montenegro, he cannot abuse the territory of Montenegro for sending any kind of political messages to his followers or the followers of the current Thai authorities,” Mr Rocen said.

Mr Thaksin, who is on the run from a jail term for corruption in Thailand, arrived in Montenegro in March when the authorities promptly issued him with a Montenegrin passport.

Mr Rocen said the former leader was currently working on “very important projects for Montenegro”.