ISLAMABAD, Pakistan - An American construction worker detained in Pakistan on what authorities said was an armed solo mission to kill Osama bin Laden has been examined by a doctor, Pakistani officials said on Wednesday, after his relatives warned he had kidney problems and needed dialysis.

Gary Brooks Faulkner was also being questioned by a team of Pakistani investigators.

Catching the al-Qaida chief was 50-year-old Faulkner's "passion," his brother Scott Faulkner said on Tuesday. A devout Christian with a prison record, Faulkner has been to Pakistan at least six times, learned some of the local language, and even grew a long beard to blend in, relatives and acquaintances said.