James Eagan Holmes, the suspect in the Colorado shooting rampage, is described as a quiet, standoffish, graduate student from San Diego who recently dropped out of a doctoral program at the University of Colorado medical school, where he had done research.
He graduated with honors from the University of California-Riverside two years ago.
A profile of the 24-year-old suspect is beginning to emerge hours after a gunman opened fire in a crowded movie theater showing the new Batman film, The Dark Knight Rises, killing 12 people, including a 6-year-old girl. Police say 59 others were wounded or injured by tear gas the gunman set off before opening fire.
Update at 5:56 p.m. ET: So far, there are no indications that Holmes had any run-ins with the law before today, not even a traffic ticket, the Associated Press says.
Jackie Mitchell, a furniture mover who lives several blocks from Holmes' Aurora apartment building, said he shared a beer with him Tuesday at a neighborhood bar. They talked about the Denver Broncos' Peyton Manning.
"We just talked about football. He had a backpack and geeky glasses and seemed like a real intelligent guy and I figured he was one of the college students," he told AP, adding that he had a "swagger."
Update at 5:11 p.m. ET: The University of Colorado School of Medicine says Holmes was not "a medical student," USA TODAY's Haya El Nasser reports.
From June 2011 to June 2012, Holmes was a graduate student in the neuroscience program and did research in buildings on the Anschutz Medical Campus, says Dan Meyers, the medical school's communications director. "He was in some of the research towers," Meyers says, and "voluntarily left that program."
Parts of research facilities are secured and require card entry. "His access was terminated," Meyers says. "He was in the process of completing withdrawal."
Meyers would not say if any particular event led to Holmes' withdrawal and repeated, "He voluntarily withdrew."
Update at 4:58 p.m. ET: Former San Diego neighbors remember James Holmes as a "normal kid" who was very shy, well-mannered and deeply involved with his family in their local Presbyterian church, the Los Angeles Times says.
"He seemed to be a normal kid, I don't know what triggered it. This makes me very sad," said Tom Mai. His 16-year-old son described Holmes as "as a normal guy, an every day guy, doing every day things."
Update at 4:24 p.m. ET: A federal law enforcement official tells USA TODAY's Kevin Johnson that the four weapons were purchased in May, June and July at Denver and Aurora-area gun shops. Investigators have recovered at least one video from a store security camera recording a purchase.
The assault rifle was traced to a Gander Mountain gun store in Thornton, Colo., and the Remington shotgun and one of the Glock handguns were bought at a Bass Pro Shop in Denver. The second Glock was purchased at Gander Mountain store in Aurora.
The official, who was not authorized to speak publicly, said a cache of ammunition was recovered in the suspect's car and used magazines were found discarded in the theater.
Update at 4:15 p.m. ET: Holmes was armed with an AR-15 assault rifle, a 12-gauge shotgun and a Glock .40-caliber handgun, said Aurora Police Chief Dan Oates. A .40-caliber handgun was found in his car, which was parked just outside the rear entrance to the cinema.
He bought a ticket to the midnight show, the first for the latest Batman movie, and entered the theater with the crowd, a U.S. law enforcement official tells the Associated Press. Holmes then allegedly propped open an exit door after the movie started, donned protective gear and started shooting.
Another source tells AP the assault rifle was equipped with a high-capacity, drum-style ammunition clip.
Update at 3:27 p.m. ET: The University of California-Riverside confirms that James Eagan Holmes graduated with honors in spring 2010 with a B.S. degree in neuroscience.
In a statement, Chancellor Timothy White says, "On behalf of the entire UCR community, I extend our deepest sympathy to the victims, their families and all of those impacted by this tragedy. "
Original post by Douglas Stanglin:
USA TODAY's Kevin Johnson quotes federal law enforcement officials as confirming the identity of the shooting suspect as Holmes, but he apparently did not have a record.
The Denver Post, citing "information provided" to the newspaper, reports that the suspect described himself last year in an apartment rental application as a student who was "quiet and easygoing."
Denver's Fox31 says police documents show he moved to Colorado from San Diego to pursue a Ph.D. in Denver.
The Associated Press reports that Holmes began a program in neurosciences at the University of Colorado in the fall of 2011 but withdrew last month.
University spokeswoman Jacque Montgomery confirms Holmes was a graduate student at the school of medicine until last month. On May 8, he was scheduled to present a paper on MicroRNA biomarkers for a class on psychiatric and neurological disorders.
The suspect, dressed in black and wearing a protective vest, was arrested by police near his car behind the movie theater during a midnight showing of the Batman film. They seized an assault rifle, shotgun and two pistols at the scene, the Associated Press reports.
"He did not resist. He did not put up a fight," says Aurora police spokesman Frank Fania.
New York Police Commissioner Ray Kelly, who was in touch with Colorado authorities, said the gunman had dyed his hair red and called himself "The Joker," referring to Batman's arch-nemesis.
The suspect recently moved into an apartment about 4 miles from the theater where the shootings took place. It is in view of Children's Hospital, where some victims were taken.
The suspect allegedly told authorities there were explosives at his third-floor apartment, which was quickly surrounded by police.
Aurora Deputy Fire Chief Chris Henderson says the apartment is "extensively" booby-trapped, with numerous liter bottles connected with wires or cord arranged in the front room, along with other unknown devices or items, USA TODAY's Trevor Hughes reports.
Police evacuated several nearby buildings as bomb squads prepared to send a robot into the apartment.
The Denver Post quotes a pharmacy student living in the apartment building as saying Holmes kept to himself and would not even respond to anyone who tried to say "hello."
ABC News reports that it spoke to a woman in San Diego who identified herself as Holmes' mother. The woman immediately expressed concern that her son might be involved in the shootings in Colorado.
"You have the right person," she told ABC News. "I need to call the police. ... I need to fly out to Colorado."
KPBS reports that San Diego police have begun providing security for the woman, identified as Arlene Holmes, who lives in Rancho Penasquitos.
The suspect's family released a statement expressing sympathy for the victims and their families:
Our hearts go out to those who were involved in this tragedy and to the families and friends of those involved. We ask that the media respect our privacy during this difficult time. Our family is cooperating with authorities in both San Diego, Calif., and Aurora, Colo. We are still trying to process this information, and we appreciate that people will respect our privacy.
The North County Times newspaper, which serves the San Diego area, quotes a neighbor who had lived next door to the Holmes' family for years as saying James had a degree in neuroscience from a University of California school.
He says Holmes' mother told him James had been unable to find a job so she sent him to Colorado to pursue an advance degree.
The neighbor, Tom Mai, describes Holmes as a "typical American kid," who "kept to himself" and "didn't seem to have many friends."