An American construction worker held in Pakistan on suspicion of wanting to hunt down and kill Osama bin Laden underwent medical tests Wednesday amid concerns for his health, officials said.
Gary Brooks Faulkner was detained Monday in the remote mountains of Chitral, once a rumoured hiding place of bin Laden, near Afghanistan's Nuristan province, armed with a pistol, dagger, sword and night-vision equipment.
Long haired and bearded, deeply Christian but suffering from kidney problems and high blood pressure, Faulkner is being interrogated by intelligence agents in Pakistan's northwestern city of Peshawar.
"A doctor examined the American and spent about 30 minutes with him," an intelligence official in Peshawar told AFP.
"The doctor told us he has some psychological problems but said he is not a mad man," the official added.
Faulkner's brother told CNN that the would-be hitman -- dubbed "the American Ninja" in the US press - was not crazy, psychotic or schizophrenic.
Scott Faulkner said his sibling needed dialysis treatment, but was motivated by patriotism and a belief in God in his quest - not the prospect of Washington's 25-million-dollar bounty for the world's most wanted man.
"Now his health is failing and he's on dialysis and in fact about five days ago he had to go down to southern Pakistan to get dialysised because he was getting weak and then he went back up," Scott Faulkner said.
He has been trained in the Korean martial art Hapkido, and favoured a sword and three-edged dagger on six visits to Pakistan to track down bin Laden, he added.
"I assumed it might be the last time I saw my brother... I asked him specifically what he wanted me to do if he came back in a body bag," he said.
The Denver Post reported that Faulkner served at least two prison sentences for burglary and larceny convictions in Colorado, and been sentenced to one year in jail in 1996 for domestic violence.
A Pakistani investigator told AFP that agents were seeking clarification about what exactly Faulkner, who is in his 50s, intended to do, investigating his previous visits to the country and where he purchased his weapons.
"They are asking him a lot of things, especially about the sword and dagger that look like ceremonial weapons. He said he wanted to kill Osama but killing Osama with a sword and dagger is not child's play," the official said.
"Carrying a pistol and such a long sword is definitely a crime but we need alot more clarifications."
Scott Faulkner told CNN: "He's like a bulldog and when he got this idea to go after Osama he's not going to let it go."
He said his brother, an independent contractor, was angered by the September 11, 2001 attacks and "taunts" by bin Laden against Christianity.
Police in Pakistan said Faulkner arrived as a tourist in Chitral on June 3, checked into a hotel, was given the customary security escort, then vanished.
Officer Mumtaz Ahmad Khan described the American as sane but "frustrated".
"Investigators in Peshawar are trying to read his mind and get answers to their questions," Khan told AFP.
The US embassy in Islamabad said American consular officials were working with the Pakistani authorities to gain consular access to the man.