Inspector General Made Mangku Pastika, deputy chief of the Criminal Investigation Division of the Indonesian national police, said the plan was uncovered after authorities found two one-way tickets to Manado at the Bali residence of the suspect, a mechanic identified as Amrozi.
"(Amrozi) had two tickets leaving for Manado at the seventh of November so we believe there is a link because he has nothing to do in Manado, so he will go somewhere else in Minda-nao," Pastika told reporters at the start of a conference on international terrorism in Makati City.
"Manado is the northern capital city of Sulawesi, very close to the Philippines, so we suspect there is a link (with local terrorist groups in the Philippines)," he added.
Pastika said Amrozi, who is still undergoing "very intensive interrogation," could have purchased the tickets for himself and a companion for their escape to the Philippines.
Amrozi was arrested Tuesday in a small village on the eastern section of Java island, where he and his brothers operated an Islamic school, Pastika said.
Investigators were able to trace the ownership of the Mitsubishi L-300 van used in the bombing to Amrozi.
Under interrogation, Amrozi has admitted building the car bomb that killed nearly 200 people last month, mostly Australian tourists.
Investigators also found traces of ammonium nitrate, a chemical primarily used as fertilizer, at the place where Amrozi claimed they assembled the bomb.
Pastika said Amrozi had plans to "kill as many Americans as possible" in the attack, but was not happy "because Australians were killed" instead of Americans.
"He did it because (he says) America oppresses the Muslims and he wants revenge," Pastika said.
The foreign ministry of Australia said a total of 59 Australians were killed in the bomb attack and 27 are still missing and presumed dead. Only three Americans were reported killed in the blast.
In Jakarta, police spokesman Brig. Gen. Edward Aritonang added Amrozi had personally known two Muslim clerics, Riduan Isamuddin, also known as Hambali, and Jemaah Islamiyah (JI) spiritual leader Abu Bakar Bashir.
The JI, a militant Islamic fundamentalist group operating in Southeast Asia, has been linked by authorities to the al-Qaeda network of international terrorist suspect Osama bin Laden.
Aritonang said Amrozi, 40, also admitted his participation in the series of bomb attacks in Jakarta in 2000, as well as the bombing of the residence of Philippine Ambassador Leonides Caday in August that same year.
Pastika said their discovery of the airline tickets and confessions made by Amrozi confirmed their suspicions that the bombing was part of the orchestrated campaign by JI to sow terror in Asia.
But the Indonesian police official, during the conference in Makati, admitted to reporters they have yet to gather solid evidence linking JI to the bombing.
"Up to now, we cannot (directly) link the act (Bali bombing) with the so-called Jemaah Islamiyah," Pastika said.
"Maybe if we arrest some other suspects, well find out if there is a direct connection (with the JI)," he added.
Pastika said the Bali bombing was hatched for about two months by six to 10 men.
Police said the ammonium nitrate was purchased at a chemical shop in Surabaya using Malaysian ringgit and Singaporean dollars.
Pastika said the authorities are now looking for at least five other Indonesians who acted as accomplices in the bombing. "We all know their names," he said.
The Indonesian police official said Amrozi had met with explosives expert Fathur Rohman Al-Ghozi in Malaysia.
Al-Ghozi, an Indonesian, was arrested and tried in the Philippines for complicity in the Dec. 30, 2000 bombings, a series
of five nearly simultaneous blasts occurring in various places in Metro Manila which left 22 people dead and scores of others wounded.
He also led Philippine police authorities to a bomb factory in General Santos City that yielded more than a ton of explosives.
Pastika said Amrozi stayed in Malaysia where he met Al-Ghozi and other countrymen with direct links to JI.
He said Amrozi also ran an Islamic school where he was often visited by Bashir. The suspect later claimed his ideological background came from "the teachings of Bashir."
During interrogation, Amrozi disclosed that Hambali, said to be the JI operations officer and second in command, is now hiding somewhere in Southeast Asia after the Bali blast.
Amrozi admitted having met Hambali several times "but not on this case," referring to the Bali blast.
The suspect reportedly told his interrogators that a change in command in JI took place where Hambali was replaced.
The successor, whom Pastika refused to name, was directly involved in the Bali bombing.
According to Amrozi, Hambali personally led the bombing of the Jakarta residence of Ambassador Caday in August 2000. "These people are dangerous as long as they are alive," Pastika added. With reports from AFP