REPORTING FROM NEW DELHI -- Thai police said Friday that they were looking for a fifth suspect in connection with explosions this week at an apparent bomb factory in Bangkok that authorities have linked to several Iranians.
Thai investigators said the explosives recovered from a rented house used by the suspects were rudimentary in design but not common to Thailand.
Police forensics expert Peerapong Damapong told a local radio network that the explosives used hollowed-out transistor radios filled with C-4, a type of plastic explosive, capped with a bolt, pin and detonator. These were configured with a five-second delay, he added, while an attached magnet allowed the device to be placed under a car and activated by pulling on a string attached to the pin.
"From what we've seen, it's possible for the components to be bought in Thailand,” he said. “The explosive isn't that complicated, it's just something that we haven't really seen in this country."
Thai police have said the bomb-making operation may have targeted Israeli diplomats, but provided no details.
Israeli was quick to tie two incidents Monday -- a bomb attached to an Israeli Embassy car in New Delhi that badly injured a diplomat’s wife and another found and defused on an embassy car in Tbilisi, the Georgian capital -- to the botched operation Tuesday in Bangkok in which a suspect blew off his leg with a grenade after fleeing the apparently accidental explosion in the rented house.
Thai news reports said the fifth suspect, possibly a bomb-making expert, was seen on security cameras entering and leaving the house a few hours before the blast.
"It is still unclear whether the [fifth] suspect is Iranian or not, but he is a Middle Eastern male," Deputy Police Chief Pansiri Prapawat said at a news conference.
The Iranian who lost his leg remains in serious condition. A second suspect was arrested at Bangkok's main airport and a third is being held in Malaysia, where he faces extradition. Thai authorities have also issued an arrest warrant for the Iranian woman who rented the house; she is believed to have left the country, possibly for Tehran.
Iran has denied any involvement in the week’s events and blames Israel for several recent assassinations of its nuclear scientists.
Indian authorities, meanwhile, reported little progress in their investigation of the Monday bombing in New Delhi, with a suspect in the motorcycle attack turning out to be a “harmless courier boy.”
Police and a 10-member Israeli team reportedly re-created the blast, which left traces of potassium nitrate and potassium chlorate. The magnet bomb used in the attack did not have a battery or circuit, local news reports said, with investigators speculating that it used a built-in, grenade-like delay mechanism.
-- Mark Magnier
Photo: A composite image taken from surveillance cameras and released by Thai police shows three bombing suspects walking in a residential area of Bangkok. Blasts on Tuesday injured five people, including one of the suspects. Credit: Royal Thai Police / European Pressphoto Agency