Colorado theater shooting: People who knew suspect are baffled The suspect in the Colorado shooting Friday was described as a shy but polite, highly intelligent young man with a gift for science. He grew up in an affluent suburb of San Diego, played soccer and ran cross-country in high school, and graduated with honors at UC Riverside with a degree in neuroscience. Few details in the emerging sketch of James E. Holmes - the 24-year-old alleged to have killed at least 12 people and injured 58 others at a movie theater - offer any answer to the question Americans find themselves once again asking after a gun rampage: Why? Friends and neighbors were baffled, and Holmes left no clues online as to his potential motives or mental state. Authorities say he booby-trapped his apartment in Aurora, Colo., with explosives and chemical devices, and they were still working to disable them late Friday before they could collect evidence that might yield insight into his thinking. The suspect had been pursuing a doctorate in neuroscience at the University of Colorado Denver Anschutz Medical Campus in Aurora for a year, but had begun the process of withdrawing from the program last month, officials said. It is not clear what triggered his decision to drop out, although some reports suggested he was having troubles with his studies. The attack appears to have been carefully planned. Carrying an AR-15 assault-style rifle, a shotgun and two Glock pistols, the killer walked into a multiplex theater screening the new Batman movie,"The Dark Knight Rises,"with dyed red hair and saying he was the Joker, according to law enforcement. He wore a gas mask, a ballistics helmet and vest, and groin, throat and leg protectors. He released two smoke- or gas-emitting devices, and then opened fire, shooting at anyone who tried to escape. He was arrested without incident near a white Hyundai in a parking lot nearby. The Aurora police chief said Holmes bought each of the four guns from retailers over the last two months and purchased 6,000 rounds for the assault rifle and the two Glocks over the Internet. Kaitlyn Fonzi, 20, a graduate student who says she lives in the apartment below the suspect, told the Associated Press that she heard techno-like music reverberating from his apartment around midnight. She went upstairs and felt the door was unlocked, but she didn't open it. "I yelled out and told him I was going to call the cops and went back to my apartment," she said. When she called police, she was told they were busy with a shooting and could not respond to her complaint. She said she was shaken to hear that the apartment was booby-trapped, and she suspected the music had been set on a timer at the time of the shootings. "I'm concerned if I had opened the door, I would have set it off," she said. Holmes' father, Robert, a software engineer, left the family's home in Rancho Peñasquitos Friday morning with a police escort, while his mother, Arlene, a registered nurse, remained at home. A neighbor described Holmes as a very shy, well-mannered young man who was heavily involved in the local Presbyterian church. He seemed to be a normal kid. I don't know what triggered it," said Tom Mai, a retired electrical engineer. This makes me very sad. His comments were echoed by many who had passing acquaintance with Holmes. Few seemed to know him intimately, but he was not totally withdrawn; he had friends and played sports. His junior varsity soccer photo shows him looking confidently into the camera wearing his No. 16 jersey. One fellow Westview High School student, who asked not to be identified, listened as people reviled the suspect all morning, and only at lunch did he learn they were talking about his old classmate. I got a call from another friend who asked, 'Do you know who it is? Jimmy Holmes,'" he said. I was silent and no longer hungry. He said he and Holmes were part of a four-person group that ate together during their sophomore and junior years. "We had the same humor," the friend said. We were all people who didn't have go-to best friends, so we all ate lunch together. He said that Holmes had a "dark, sarcastic kind of humor" but that he never "read it as psychotic," and he wasn't notably introverted within their circle. Looking back, I guess he was dorky, and so was I. He wasn't quiet, but he didn't make a big effort to make friends. UC Riverside Chancellor Timothy P. White said that Holmes was an honor student as an undergraduate there. He had no run-ins with police on campus or anything else that would foreshadow what happened. White said professors who knew Holmes expressed disbelief about what occurred. "We are very deeply saddened by this horrific event," he said. He said neurological sciences is a rigorous area of study on campus. "He was an honor student, so academically, he was at the top of the top," he said. Jessica Cade, 23, a graduate student at UC Riverside, lived in the same honors dorm as Holmes and said that she would occasionally go out with him with friends. He was a very nice guy. He was very, very smart; a little weird - kind of like you'd expect a really smart guy to be," Cade said. She said that Holmes and other young men in the dorm often played video games, especially Guitar Hero, but nothing out of the ordinary. They're calling him 'deranged' and a 'lunatic.' Never in a million years would that have crossed my mind," Cade said. I was horrified when I saw his picture on the news. I was very close to fainting in the office. Holmes appears to have left little record of his thoughts or activities online, with no Facebook, Twitter, LinkedIn or Myspace accounts under his name. He had no previous run-ins with law enforcement. Staff writers Nicole Santa Cruz, Tony Perry and Richard Marosi in San Diego, John M. Glionna in Denver, Phil Willon in Riverside and Larry Gordon in Los Angeles contributed to this report.