Who is John Patrick Bedell?

WASHINGTON - The man who opened fire in front of the Pentagon had a history of mental illness and had become so erratic that his parents reached out to local authorities weeks ago with a warning that he was unstable and might have a gun, authorities said Friday.

It's still unclear why John Patrick Bedell opened fire Thursday at the Pentagon entrance, wounding two police officers before he was fatally shot. The two officers were hospitalized briefly with minor injuries.

Bedell was diagnosed as bipolar, or manic depressive, and had been in and out of treatment programs for years. His psychiatrist, J. Michael Nelson, said Bedell tried to self-medicate with marijuana, inadvertently making his symptoms more pronounced.

"Without the stabilizing medication, the symptoms of his disinhibition, agitation and fearfullness complicated the lack of treatment," Nelson said.

His parents reported him missing Jan. 4, a day after a Texas Highway Patrol officer stopped him for speeding in Texarkana. Bedell told the highway patrolman he was heading to the East Coast, and began acting strangely -- sitting on his knees by the side of the highway and turning off his cell phone when it would ring.

Bedell said it was his mother calling, prompting the patrolman to answer the phone and talk briefly with her. Family friend Reb Monaco said Kaye Bedell asked the officer to take him to a mental health facility, but that the son refused.

The patrolman let Bedell go after issuing a speeding ticket and a citation for possession of drug paraphernalia, including a pipe and a green plastic box with marijuana residue.

The next day, Kaye told deputies in California that her son had no reason to travel to the East Coast because he had no friends or family there and she and her husband were worried about his mental state, San Benito County Sheriff Curtis Hill said.

Hill also said Bedell's parents found an e-mail from their son that indicated he had made a $600 purchase from a shooting range in the Sacramento area that could have been a gun or ammunition.

The 36-year-old Bedell returned to his parent's home Jan. 18, telling them "not to ask any questions" about where he had been. But he left after that, and his parents didn't know where he went.

Little is known about his trip east, but authorities know he spent time in Reno, where Washoe County Sheriff Mike Haley said he was arrested on Feb. 1 with two ounces of marijuana in his car but no weapons.

The Bedell family put out a statement Friday saying they were "devastated as a family by the news."

"We may never know why he made this terrible decision," the statement said. "One thing is clear though -- his actions were caused by an illness and not a defective character."

Investigators were trying to unravel a bizarre series of Internet postings that suggested Bedell was fascinated with conspiracy theories, computer programming, libertarian economics and the science of warfare.

Curiously, Bedell also proposed in 2004 that the Pentagon fund his own research on smart weapons. The 28-page proposal outlined his idea for DNA nanotechnology research that might "provide significant new capabilities for the Department of Defense and the individual warfighter."

That document is the first tangible link to surface connecting Bedell and the Pentagon.

On the day of the attack, Bedell left his green, 12-year-old Toyota in a nearby mall parking garage.

The six-foot tall, blue-eyed software devotee approached the Pentagon entrance Thursday evening wearing a jacket, dress shirt and pants, seeming like any other end-of-the-day commuter.

Bedell, the officials say, opened fire with a 9 mm handgun just five feet from the nearest officer, Marvin Carraway. Fellow officer Jeffery Amos ran out of a nearby guard booth to confront Bedell, as did a third, unidentified officer. All three officers gave chase and fired at Bedell, who was struck in the head and left arm.

Witness Dan Namisi said he had just emerged from the Metro station, headed for a bus home, when he heard a "pop." The Uganda native hit the ground, and the next thing he knew, officers swarmed over him and put handcuffs on him.

Namisi says he was searched repeatedly, but officers didn't ask him many questions during the three hours they held him. He said he may have attracted attention because he cut one of his hands when he dropped to the ground and the hand was bloody.

"I'm still very traumatized by it," Namisi said in a telephone interview. "In my experience they don't put you in a police car unless you're in trouble."

Defense Secretary Robert Gates on Friday called the two wounded officers to express his "appreciation for their service, their bravery and their professionalism," said Pentagon Press Secretary Geoff Morrell.

Gates was not at the Pentagon at the time of the shooting because he was attending meetings at the White House.

The assault at the very threshold of the Pentagon -- the U.S. capital's ground zero on Sept. 11, 2001 -- came