Bangkok - Forensic evidence on casualties of Tuesday's bloody showdown between police and anti-government protestors in Bangkok suggest that deadlier weapons than teargas were used in the clash that left two dead and more than 400 injured, doctors said Thursday.

Angkhana Radabpanyawoot, 25, one of the casualties in Tuesday's clash, was killed by an explosive, not a teargas canister, according to Dr Vichan Peonim, the head of Ramathibodi Hospital's forensic department.

"Her wounds were caused by hard material, accompanied by heat and pressure which means an explosive, not a teargas canister," said Vichan.

Angkhana's mother and sister, also followers of the anti-government People's Alliance for Democracy (PAD), were also injured in the explosion.

"Whether Angkhana was carrying the bomb or it was thrown at her is impossible to say from the forensic evidence. It will require questioning eye witnesses," said Vichan.

The second fatality in the clash was PAD member Methee Chartmontri, a former police officer, who was killed by an explosion in a jeep. A police investigation suggested the victim had been carrying bombs.

Thai police have claimed that the PAD followers were armed with small explosives called ping pong bombs, and that many of the most severe injuries were self-inflicted.

They have denied using anything other than teargas canisters, many of which were fired directly at the protestors.

At least 20 policemen were also injured in the melee. Two of them suffered gunshot wounds and one had his legs broken after being repeatedly run over by a protestor's pickup truck.

On Tuesday, riot police were called in to disperse thousands of PAD followers from blocking the road outside Parliament in an effort to prevent the reading of the new government's policy statement, a first step for any administration.

The PAD, a loose coalition of groups staunchly opposed to former prime minister Thaksin Shinawatra and his political allies, failed to prevent the lower and upper houses from convening, but did manage to surround Parliament and block exits.

Police fired more teargas canisters to disperse the protestors and allow legislators to escape Parliament Tuesday evening, claiming more casualties.

PAD leader Sondhi Limthongkul claimed Wednesday that he was compiling evidence that the police were responsible for the bloodshed that will be released to the public soon.

The PAD's thousands of followers have retreated to Government House, which the movement has occupied since August 26.

Although Bangkok has largely returned to normal, the confrontation between the PAD and the government remains unresolved.

The PAD is calling for the dissolution of the government under Prime Minister Somchai Wongsawat on the claim that the current government is a proxy for Thaksin.

Somchai is the brother-in-law of Thaksin, who is currently living in self-exile in London where he and his family have sought political asylum.

Thaksin faces several corruption charges dating back to his two-term premiership between 2001 to 2006, and his wife Pojaman has been sentenced to three years in prison for tax evasion. He was ousted by a coup on September 19, 2006.

The PAD, which is staunchly pro-monarchy and highly critical of the type of money politics Thaksin came to represent, has drawn many of Bangkok's middle class to its ranks and enjoys the tacit support of members of Thailand's political elite. (dpa)