he suspect apprehended in the mass shooting at a suburban Denver movie theater has been identified as James Eagan Holmes, 24, law enforcement sources told CBS News correspondent Bob Orr.
Twelve people died in the shooting at a showing of the new Batman film "The Dark Knight Rises" in Aurora, Colo., early Friday morning. A law enforcement source told Orr the shooting appears to have been carried out by a lone gunman.
One federal official told CBS News that at this time Holmes appears to have been "under the radar." CBS News reports Holmes doesn't appear to have a criminal record in Colorado or in San Diego, Calif., where he graduated from high school. Pentagon officials said there is no record of Holmes having served in any branch of the military.
San Diego police read a statement from Holmes' California family that their hearts go out to those involved. They say they're cooperating with authorities in San Diego and Aurora and are trying to process everything. San Diego police spokeswoman Andra Brown said there's nothing to suggest the family had any involvement.
According to the University of Colorado, Denver, Holmes was in the process of dropping out of the school's graduate program in neurosciences. School spokeswoman Jacque Montgomery said in a statement that Holmes enrolled at the school in June 2011. She didn't say why he was withdrawing.
The University of California, Riverside, confirmed to CBS News that Holmes graduated in 2010 with a degree in neuroscience.
There was no immediate word of any motive for the attack. Federal law enforcement officials were briefed on the attack, but at this point there is no indication it is terrorism-related, CBS News senior correspondent John Miller reports.
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Police evacuated the area surrounding Holmes' Denver-area apartment, saying the residence was apparently booby-trapped. A law enforcement source told Orr that police saw what looked like "buckets of extra ammunition" and some kind of chemical inside his home.
Aurora Police chief Dan Oates said it could take hours or days to safely enter the apartment.
Police recovered four guns at the theater, including two pistols, a shotgun and what is believed to be an assault rifle, Orr reports. Authorities also recovered a ballistic helmet and a gas mask.