The suspect accused of killing six people and wounding Arizona Rep. Gabrielle Giffords was decribed as a disturbed young man who was rejected by the military and frequently disrupted his college class.
The Tucson neighbors of 22-year-old suspect Jared Loughner said he often kept to himself - not hostile to anyone but certainly not warming up to anyone, either.
"He was a guy in high school who definitely had his opinions on stuff and didn't seem to care what people thought of him," said Grant Wiens, 22, who told The Associated Press he went to high school and had a class at Pima Community College with Loughner.
Loughner was in custody after authorities said he opened fire outside a grocery store as Giffords, a Democrat, met with voters. The rampage killed six people including Arizona's chief federal judge. Giffords was among 13 people wounded.
Authorities said the accused gunman targeted the three-term congresswoman, but an exact motivation was not immediately known. Many questioned whether the nation's polarized political climate had played a role, even as Loughner's political views remained unclear late Saturday.
Pima County Sheriff Clarence Dupnik described the gunman as mentally unstable and said he possibly acted with an accomplice.
Lynda Sorenson said she took a math class with Loughner last summer at Pima Community College's Northwest campus and told the Arizona Daily Star he was "obviously very disturbed."
"He disrupted class frequently with nonsensical outbursts," she said.
In a Dec. 15 YouTube video, Loughner describes himself as a U.S. military recruit.
Federal law enforcement officials poured over versions of a MySpace page that belonged to Loughner and over a YouTube video published weeks ago under an account "Classitup10" and linked to him. The MySpace page, which was removed within minutes of the gunman being identified by officials, included a mysterious "Goodbye friends" message published hours before the shooting and exhorted his friends to "Please don't be mad at me."
On his MySpace page, Loughner spoke of how he liked to read and he also wrote repeatedly about literacy, complaining that the rate was especially low in the congressional district where he lived.
"The majority of people, who reside in District-8 are illiterate hilarious. I don't control your English grammar structure, but you control your English grammar structure," he said.
In an interview with The Associated Press, Wiens also said Loughner used to speak critically about religion. He also talked about how he liked to smoke pot.
"He wasn't really too keen on religion it seemed like," Grant Wiens, 22, told The Associated Press. "I don't know if floating through life is the right term or whatever, but he was really just into doing his own thing."
Loughner's MySpace profile indicated he attended and graduated from school in northwest Tucson and had taken college classes. He did not say if he was employed.
Tamara Crawley, director of the Marana Unified School District in Tucson, said Loughner attended Mountain View High School in Tucson for three years but withdrew after completing his junior year in 2006. Crawley did not know why Loughner had withdrawn from Mountain View High and it was not clear if he had transferred to another school in the area.
The Army released a statement indicating Loughner was not accepted.
In October 2007, Loughner was cited in Pima County for possession of drug paraphernalia, which was dismissed after he completed a diversion program, according to online records.
A year later he was charged with an unknown "local charge" in Marana near Tucson. That charge was also dismissed following the completion of a diversion program in March 2009, the Daily Star reported.
Ryan Miller, 19, was a sophomore at Mountain View when Loughner was a senior. He said Loughner was seemed like a normal kid.
"I was in shock," he said, describing his reaction to the shooting. "I didn't know what possessed someone our age to do something like this."
This program aired on January 9, 2011. The audio for this program is not available.