On the sixth day of the investigation into the JW Marriott bombing, police estimated that the bomb contained between 10 kilograms and 20 kilograms of explosives. The explosion, which claimed 11 lives and injured 148 others, produced a two-meter wide crater, penetrating through 32-centimeter thick concrete into the basement. A police detective, however, said that around 20 kilograms of explosives would be needed to cause such devastation. By applying special chemicals to items around the blast scene and then a special paper similar to Litmus paper, investigators are able to identify the presence or otherwise of explosives' residues. Police found traces of the high explosives HMX, TNT and RDX, and low explosive powder at the blast site. The bomber had placed four jerry cans containing gasoline around the bomb, which created a fireball effect after detonation. The fireball instantly killed six of the victims. Six officers from the National Police Central Forensics Laboratory and five officers from the Australian Federal Police were still busy searching the blast site for evidence and clues.

The United States has also offered assistance with the investigation. Minister of Foreign Affairs Hassan Wirayuda told The Jakarta Post that US Secretary of State Colin Powell phoned him on Saturday to offer help and convey his sympathy to the wounded. Hassan informed him that the bombing was related to the recent arrests of alleged Jamaah Islamiyah (JI) members in Semarang, Central Java.

Meanwhile at the bomb scene, the police had still not allowed the removal of debris left by the bombing, including the wrecked Toyota Kijang van that contained the bomb, the shards of glass from blown-out windows, and twisted metal window frames. The crater, two meters in diameter, has been covered with a large sheet of plywood.

Police have linked the Marriott bombing to JI, due to similarities with other JI bombings as regards the explosives used, the use of a mobile phone to trigger the bomb, and the removal of the engine and chassis identification numbers from the van containing it. Police have announced that the suspected suicide bomber was Asmar Latin Sani, 28, who apparently drove the van that exploded in the hotel's entrance driveway.

Two arrested JI members, Sardono Siliwangi and Muhammad Rais, told police that they had recruited Asmar to the JI. Rais reportedly transported 50 kilograms of explosives from Palembang to Bengkulu in February this year. The explosives were kept at Asmar's house.

Denpasar District Court has just sentenced a JI member called Amrozi to death for his involvement in last year's Bali bombings, which killed 202 people and wounded 300 others. Jakarta Governor Sutiyoso said yesterday that his administration would cooperate with the Jakarta Police to ensure better security in public places, including malls, hotels and entertainment centers. They will be checked at random and if any fail to meet the security standards, this will be announced to the public. Sutiyoso has officially requested the Jakarta Military Command to help ensure security in public places, due to staff shortages in the police. In Jakarta the ratio of police officers to the city's population is about 1:925, much less than the ideal ratio of 1:300 set by the UN. He warned members of the public to keep an eye on rented houses and low-cost hotels, which are usually used by terrorists to plan and prepare their attacks.

The Aceh Referendum Information Center (SIRA) announced that 235 civilians were killed in the first month of the offensive launched to crush the separatist rebels in Aceh on May 19th and another 60 in the second month. The military's latest figures released yesterday show a total of 653 rebels killed since May 19th, but do not list civilian casualties. The rebels of the Free Aceh Movement (GAM) say many of those killed are civilians. The military claims more than 1,400 rebels have been arrested or surrendered during the same period, while the army and police lost a total of 55 men.

SIRA seeks a referendum on independence for the province. Its calculation of the civilian death toll was based on "reliable field sources," but the difficulties in checking the figure were admitted and the organization requested a special report from the UN or from an independent international institution. The head of SIRA, Muhammad Nazar, was jailed for five years last month for sedition.