Bali blast suspect demonstrates how bomb assembled
Wahyoe Boediwardhana, The Jakarta Post, Denpasar, Bali
A key suspect in the October attack in Bali demonstrated to police how the bombs were made from a mixture of chemicals and explosive materials, and how the bombers planned the attack that left at least 190 people dead.
In a reconstruction of the crime on Tuesday, suspect Ali Imron showed how the bombs were assembled and provided details of the attack.
According to the suspect, the attack did not go entirely as planned and the final moments before the blasts remain unclear. One of the two suspects who detonated the bombs is believed to have died in the explosions and the other is still at large.
Three bombs were used for the attack: one near the American consulate in Denpasar and the other two at crowded nightclubs along a tourist strip in Kuta.
The first bomb exploded in Paddy's Cafe on Jl. Legian in Kuta. Ali said that bomb consisted of six 25-centimeter-long plastic tubes, each filled with four kilograms of TNT.
The tubes were stuffed into a vest, which must have weighed about 24 kilograms when the bomber walked into the cafe and killed eight people, including himself. It remains unclear whether this was a suicide attack, which is the belief of the police, or whether the bomb simply went off prematurely.
The biggest blast was the explosion outside the Sari Club, located across from Paddy's. Here at least 182 people died, many of them foreign tourists.
Between Sept. 25 and Oct. 2, suspects Ali, Abdul Goni, Umar Patek and Syawad are believed to have assembled the Sari Club bomb inside a rented house in Denpasar.
The bomb's main ingredients were 900 kilograms of potassium chlorate, a type of fertilizer that is often used in fish bombs; 75 kilograms of aluminum powder; and 150 kilograms of sulfur.
The chemicals were mixed into a black powder and then placed inside 48 plastic cabinets. Each cabinet was connected with a 150-meter-long detonator cord. Every 10 centimeters of the cord contained one gram of the explosive pentaerythritol trinitrat (PETN). In addition to the cord, the bombers also used 94 detonators containing 279 grams of the explosive material RDX.
As a booster, they used 25 kilograms of TNT, which was put inside a separate plastic cabinet.
A remote detonator was assembled with three options to detonate the bomb: either through a cellular phone, a timer set for 45 minutes or with a switch to detonate the bomb immediately. Tampering with the remote detonator would also have triggered the bomb.
Malaysian suspect Asahari, who remains at large, is believed to have assembled the detonators. The Sari Club bomb was then loaded into a Mitsubishi L-300 van.
The bomb near the U.S. consulate exploded seconds after the Sari Club bomb, causing no casualties. Ali said this bomb was assembled by filling a plastic box, which measured 25 centimeters in height and 15 centimeters in width, with TNT.
He said the bomb was detonated as planned via a cellular phone call. However, he could not say who and what detonated the bomb outside the Sari Club.
Ali was inside the L-300 along with two other suspects who he identified as Jimmy and Iqbal, as the three moved the bomb into position outside the Sari Club.
Ali got out of the van before it arrived at the club, and he returned to the rented house with suspect Idris, who was following the van on a motorbike.
Jimmy was supposed to detonate the Sari Club bomb via a cellular phone, but Ali realized too late that he took the cellular phone with him when he got out of the van.
Ali said the bomb exploded before the 45 minutes on the timer had elapsed, which meant the bomb had been detonated by someone who pressed the switch or by someone who tried to open the remote detonator.
Witnesses said the Mitsubishi van was parked outside the Sari Club. The 1.25 tons of black powder, 25 kilograms of TNT, 1.5 kilograms of PETN and 279 grams of RDX literally blew the van to pieces. It also left a five-meter wide and 70-centimeter deep crater beneath the van.