BANGKOK, Thailand (AP) — The blast that destroyed a jetliner just before Thailand's prime minister was due to board over the weekend was caused by a bomb that included sophisticated plastic explosives, the defense minister said Monday.
Still, it was still too early to be sure the bomb targeted Prime Minister Thaksin Shinawatra, the minister said.
The blast Saturday ripped through the floor and ceiling of the Thai Airways Boeing 737-400 and left a big hole in the tarmac of Bangkok airport, Defense Minister Chavalit Yongchaiyudh told a news conference.
The plane exploded in flames near a boarding gate 35 minutes before Thaksin and 148 other passengers were due to fly from Bangkok to the northern city of Chiang Mai. One cabin crew member was killed and seven other airline staff injured. No passengers had boarded the plane when the bomb went off.
"The report I received today says it was clear there was a plan to make things happen, but please don't jump to the conclusion that the plan was aimed at harming the prime minister. We have more factors to examine," Chavalit said.
He said that investigations had shown the bomb "was certainly C-4," and he noted that only highly placed organizations or international terrorists would have access to the high-quality, military-grade plastic explosive.
Thaksin said Monday that the blast was caused by a bomb with a mix of TNT, C-4 and other explosives and chemicals. He said he was one of the possible targets, but there was no proof yet the bomb had been intended for him. "We're narrowing down the list of possible motives," he said.
"It might have targeted someone else . . . I do not know who else was supposed to be on that plane," Thaksin told reporters, saying whoever was behind the attack was "out of his mind."
The Federal Aviation Administration and the National Transportation Safety Board have sent representatives to Thailand, the U.S. Embassy said. Boeing officials arrived late Sunday.
Thaksin suggested that if he was the target, attackers would have had inside information about his schedule, as he had originally planned to go to Chiang Mai on Sunday but told his secretary Friday to change the flight to Saturday afternoon.
Local media have speculated the attack could be linked to Thaksin's pledge to stem the trade in heroin and methamphetamines, largely blamed on drug lords in neighboring Myanmar, also known as Burma.
Thaksin said the incident would not scare the government from pressing ahead with its "urgent agenda" in cracking down on drug syndicates.
Thaksin pressed ahead with his work schedule Monday, with tighter security provided by the police special branch. The prime minister was now using a bullet proof car, said Police Maj. Gen. Tritot Rerngrithichai, who is responsible for the security of VIPs in Thailand.
Thaksin's security adviser, Prasarn Wongwai, said Sunday that the source of the explosion "came from where the prime minister was supposed to be seated."
Chavalit said it was still not sure where the explosive had been planted. It could have been underneath a passenger seat, in the cargo compartment or at the wheels at the base of the plane, he said.
Police Lt. Gen. Sant Sarutanond, the deputy national police chief, said suspicions focused on a frozen meat package that had been loaded on the plane after only a sample of it had passed a security inspection.
"We're checking everything loaded on the plane but we have reached no conclusion yet," he said.
Thaksin took power last month after his party won general elections by an unprecedented margin after campaigning on a raft of populist promises, including an end to corruption and a promise to revive the sluggish economy.
Thailand has a history of coups and violent overthrows of governments, but no prime minister has faced an assassination attempt. The nation has enjoyed political stability under a succession of democratic governments for the last eight years.