A Briton suspected in an alleged plot to blow up trans-Atlantic jetliners fled custody after two police officers stopped en route to jail so he could say prayers, but he slipped out the mosque's back door instead, police said Monday.

New details of Rashid Rauf's escape, a major embarrassment for President Pervez Musharraf's government, emerged two days after he got away following a court appearance in Islamabad on Britain's request for his extradition.

A police official, speaking on condition of anonymity due to the sensitive nature of the issue, said Rauf was being taken back to Adiala Jail — a high-security prison in the garrison city of Rawalpindi — when he asked his guards to let him say afternoon prayers at a roadside mosque.

"The policemen accepted his request," the official said. "Rashid Rauf went inside the mosque with handcuffs on, but he slipped out from a rear door."

The official said police raided homes of Rauf's relatives with no success. He said the two police officers made statements during interrogation, admitting they were waiting in a car outside the mosque when Rauf went inside.

The official said police had taken an uncle of Rauf into custody to determine whether he played any role in the escape.

Rauf's lawyer, Hashmat Habib, identified the uncle as Mohammed Rafique.

But Habib said Rafique had been in the Kashmir region on Saturday and that he doubted his client had fled.

"I know Rashid Rauf was prepared to go to London," he told The Associated Press and accused police of covering up his "mysterious disappearance.":

Habib said police commandos had escorted Rauf on earlier trips to court. "How can it happen that only two policemen were traveling with him on Saturday?"

Interior Minister Hamid Nawaz assured Ambassador Robert Brinkley that the suspect's capture was a "priority," British High Commission spokeswoman Laura Davies said Sunday.

Interior Secretary Kamal Shah said security teams were searching the country and would report back within three days.

Rauf, who is of Pakistani origin, was arrested here in August 2006 on a tip from British investigators. Pakistan described him as a key suspect in a purported plot to blow up airplanes flying from Britain to the United States, prompting a major security alert at airports worldwide and increased restrictions on carry-on items. He was charged with possessing chemicals that could be used in making explosives and with carrying forged travel documents.

Rauf denied involvement in the plot and prosecutors later withdrew the case against him, though he remained in jail awaiting a decision on a British extradition request.

Britain asked Pakistan to hand him over in connection with a separate 2002 murder inquiry. The two countries do not have an extradition treaty.

Members of Rauf's family have appealed for his release, saying he is innocent and desperate to remain with his wife and two daughters.