Thailand's political chaos moved into a new and dangerously violent phase this morning after at least ten anti-government militants were wounded by a hand grenade thrown into their makeshift protest camp near the UN headquarters in central Bangkok. A man, who according to Thai TV had been seen arguing with the protesters, was found dead near the camp.

Soon after the attack hundreds of protesters from the People's Alliance for Democracy (PAD) converged on the British embassy in Bangkok, where they blocked the road and demanded the extradition from the UK of Thaksin Shinawatra, the ousted prime minister convicted of corruption last week by a Thai court.

Tensions have been simmering for months in the divided nation, where the militant anti-government protestors of PAD have sworn to get rid of the elected government led by Somchai Wongsawat. Mr Somchai, the brother-in-law of Mr Thaksin, has become a hated figure to the militants who accuse him of being little more than Mr Thaksin's puppet.

Pro-government activists have mobilised and the rhetoric from both camps has become increasingly vociferous – but until today the opposing groups had not come to blows.

The hand grenade, thrown from a passing motor cycle, was a signal the gloves had come off, said political scientist Dr Thitinan Pongsudhirak from Chulalongkorn University. "It's become more violent,'' he said. "I don't know when it's going to get better. It's naked confrontation now." The government could appeal for calm, he said, but he feared the conflict had gone past the point of no return.

The pin of an M25 grenade was found at the scene. Police said they suspected the attackers were supporters of the Democratic Alliance Against Dictatorship who support the People’s Power Party government led by Mr Somchai.

Two of the PAD militants, injured while on duty as security guards at the camp at a key Bangkok intersection known as Makawan Bridge, are now in a critical condition in hospital. In a separate but possibly related incident, a grenade was today thrown through the window of a Constitutional Court judge, shattering windows but causing no injuries.

Jaral Phakdeethanakul,a Constitution Court judge, had been involved in the rulings against Mr Thaksin.

PAD militants remain resolved to fight on regardless of the danger, and this morning a crowd of over 300 protesters blocked the roads leading to the British embassy, watched by a squad of 120 police officers. In what has become a leit-motif of PAD rallies, the protestors carried banners of Thaksin and his wife Pojaman with the words: "Wanted for crimes against the kingdom of Thailand."

"Why doesn't England send Thaksin back to Thailand to be put in jail?" PAD spokeswoman Sarocha Pornudomsak shouted to the crowd. "We are here to tell Gordon Brown that England should not keep a bad guy in the country."

The PAD militants have been up in arms since May, and they now insist their actions are vindicated following Mr Thaksin's conviction last week for breaking anti-corruption laws.

"Some of the government disciples threaten us but we will never surrender," said retired government official and ardent PAD supporter Suwan Kansanoh. He speculated the grenade thrown at the protest camp was of government origin.

"Some people think it was a third party, but the Border Patrol has grenades," he said. "Civilians don't have grenades. I think government supporters threw the grenade, but the grenade came from the government." He also believed disguised police officers had joined the pro-government movements.

Mr Suwan said the government was bussing in supporters from the north of Thailand today and tomorrow, and he feared more violence would ensue. "But we are ready to confront the government supporters," he said.

Protests have continued since August, when the militants first occupied the prime minister's compound, set up a tented city in the grounds, and began a series of massive rallies. One protestor was killed, and hundreds injured on October 7, when police fired tear gas at a PAD crowd attempting to blockade Parliament House.

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