Police pursued a tip Wednesday from a caller claiming that one of the latest Bali (search) bombers studied on an Indonesian island known for having hard-line Islamic schools.
It was one of the few possible leads announced since police started circulating nationwide photographs of the three bombers' severed heads, recovered from the attacks Saturday on crowded tourist-resort restaurants. The blasts killed 22 and injured 104.
The tipster called police in Solo (search), a city on the main island of Java. He identified one of the bombers by name and said he had studied in the area, home to an radical Islamic boarding school attended by several militants convicted in previous terror attacks, said Abdul Madjid, Solo's police chief commissioner. He gave no further information.
Saturday's attacks put Southeast Asian nations on high alert, with hundreds of thousands of troops on standby and tightened security on beaches and along borders.
The Al Qaeda-linked Jemaah Islamiya (search) was emerging as the key suspect in Saturday's attacks, which came three years after Bali nightclub bombings that killed 202 people, blamed on the regional Islamic extremist group.
In a sign of the tense atmosphere, bomb disposal squads and hazardous materials experts rushed Wednesday to the U.S., British, Australian, French and Russian embassies in Malaysia after receiving packages threatening retaliation for perceived injustices against the Muslim world, police said.
The parcels were dismissed as a hoax, as were envelopes sent to six other diplomatic missions a day earlier, said Abdul Aziz Bulat, chief of Kuala Lumpur police criminal investigation.
Investigators across the country were interrogating jailed terror convicts, seeking information about Saturday's bombers, said Bali police chief Maj. Gen. I Made Mangku Pastika.
"So far the detained terrorists do not know them," Pastika said.
Those questioned included Amrozi bin Nurhasyim and Imam Samudra, sentenced to death for their roles in the 2002 Bali attacks.
Meanwhile, the recent bombings have triggered new calls for Washington to give Indonesian investigators access to detained Southeast Asian terror mastermind Hambali — a Muslim cleric once dubbed Usama bin Laden's point man in Southeast Asia.
Washington's refusal, a long-standing irritant between the two nations, comes as the United States tries to boost anti-terror cooperation with Indonesia, the world's most populous Muslim nation.
"I think the time has now come for the United States to give full access to the Indonesian police so they can interrogate Hambali," said Theo Sambuaga, chairman of Parliament's political and security commission.
The United States says giving Indonesian investigators access to Hambali, also known as Riduan Isamuddin, could compromise their own investigation of him, reportedly involving alleged links to two of the Sept. 11 hijackers and a plan to recruit new pilots for another wave of hijackings in the United States.
Hambali, a 41-year-old Indonesian citizen, is also accused of being Jemaah Islamiya's operations chief. Thai forces and the CIA captured him two years ago in the ancient Thai temple city of Ayutthaya. He was handed over to U.S. authorities and flown to an undisclosed location for interrogation.
Asked about access, the U.S. Embassy in Jakarta on Tuesday reissued a statement from last year saying it "was committed to allow the Indonesian government to bring Hambali to justice for terrorist attacks perpetrated in Indonesia by Jemaah Islamiyah at the appropriate time. However, we have set no timetable for such a turnover."