A CIA tip-off led to the arrest in Pakistan of the main Indonesian suspect in the 2002 nightclub bombing in Bali, Pakistani security officials say, but it is not clear whether the Americans will get access to the alleged militant.
The officials did not say where or when Umar Patek, allegedly a deputy commander of al-Qaeda's Southeast Asian affiliate Jemaah Islamiah, was detained.
But the Philippine army, which has also been hunting him, said he was picked up in Pakistan on January 25 alongside a Pakistani associate assumed to have been harbouring him.
The arrest of Patek, who has a $US1 million American price tag on his head, ends a 10-year international manhunt.
But questions remain over how he was able to travel to Pakistan undetected and what he was doing in the country, which continues to attract foreign militants seeking contact with al-Qaeda leaders based there, especially in the northwest close to Afghanistan.
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Indonesian police detective chief, Lietenant General Ito Sumardi, said officers there suspected Patek travelled on a commercial flight via Bangkok after obtaining a genuine passport using a false name.
He said his information indicated that Patek was arrested with other al-Qaeda suspects, and that he was not the target of the raid.
News of his arrest initially came from intelligence officials in Indonesia and the Philippines on Tuesday.
On Wednesday, Pakistani security officials confirmed the capture. All spoke on condition of anonymity because of the sensitive nature of the issue.
"The CIA tipped us off that he might be travelling here," one official said, but stressed that it was a "solely Pakistani operation."
Another Pakistani official said Patek was currently being questioned by Pakistani agents, but that he would "eventually" be given to the Indonesians.
"It is our policy to send them back to their country of origin," he said.
Sumardi, the Indonesian police chief, said his country would request custody of Patek.
"We strongly hope that the Pakistani authorities are willing to give us access to him, and we would welcome his handing over to his country of origin," he said.
The CIA would presumably like to have access to Patek, but the Pakistani officer said this would happen only with the written consent of Indonesia.
Jemaah Islamiah members, allegedly including Patek, are suspected to have carried out the Bali nightclub bombings that left 202 people dead, including 88 Australians.
He is also suspected in at least two other suicide bombings in Jakarta in 2003 and 2004.
Australian Foreign Minister Kevin Rudd welcomed Patek's arrest.
"It is our view that the Patek arrest is potentially a major step forward in the fight against terrorism," he said in Bali, where he is attending a regional meeting.
