A homemade tube like detonator exploded beside a security box in front of the residence of Thai Privy Council's Chairman Prem Tinsulanonda in central Bangkok on Thursday afternoon, injuring two foreigners and causing minor damage.

The blast occurred at 2:05 PM local time (05:05 GMT) near a security box outside Prem's house compound in Bang Lamphu district in Bangkok. A policeman at the scene told Xinhua that the bomb was laid under a stone chair which was burst into pieces after the blast.

Some police dynamite experts sampled the metal relics of the bomb and said it was something like a homemade percussion cap.

"The bomb which blasted today is the same kind of the two bombs which exploded in Bangkok during the last two months," a plainclothesman said.

Fung, a shopkeeper whose store is just in front of the blast scene, said a few stone pieces were burst into her shop.

"I was doing some cleaning in the shop when I heard the huge sound. It just like an earthquake and some stone pieces flied into the front-yard of my shop," Fung said. "And then I saw two foreigners, a man and a woman, sat on the ground beside the security box of Prem's residence."

Initial investigation identified the injured as a Briton and a Canadian. A spokesman of Vajira Hospital identified the Briton as Jeffeny King, 28, who was passing the house at the time of the blast. He was injured by shrapnel in his left shin.

Three cars were also damaged in the explosion, police said.

Police closed the four-lane road in front of the scene half an hour after the blast and then some soldiers from Thai Royal Army marched into the residence.

"Some passers-by witnessed a man in his twenties rode a bike around the residence for several times and the police are hunting the suspicious person now," a security man guarding the closed gate of the residence said.

Another police officer said he believed the blast was related to recent political chaos in Thailand. He thought the group behind the blast wanted to make more confusion for the situation because "Prem plays an important role between the political side and the royal side."

Prem, a former army commander-in-chief who was prime minister between 1980 to 1988 and currently Privy Council chairman to Thai King Bhumibol Adulyadej, was in his residence when the bomb exploded. He said after the blast that he "never knows why to be the bomb target."

Prime Minister Thaksin Shinawatra, who was on the election campaign tour in Chanthaburi, said he had not received an official report on the bomb yet but he believed someone was trying to create a situation.

He said police would try to find out the masterminds of the bomb and bring them to justice.

The embattled caretaker prime minister is facing, on one hand, a strong pressure from anti-Thaksin middle-classed groups, led by the People's Alliance for Democracy (PAD), to force him to step down following his family's sale of Shin Corporation shares to Singapore's Temasek Holdings in late January and, on the other hand, an overwhelmed support by pro-Thaksin groups who are mostly people of the grassroots level and want him to remain in office.

(Xinhua News Agency March 10, 2006)