Hollywood News Now: AP source: Batman mask found in Colorado massacre suspect's home

As many as 12 people were killed and 50 injured at a shooting at the Century 16 movie theatre in Aurora, Colo. early Friday during the showing of the latest Batman movie.

By NBC News wire services

AURORA, Colo. -- Investigators have found a Batman mask inside the apartment of a man suspected of opening fire at a midnight premiere of "The Dark Knight Rises,"Â a law enforcement official toldÂ The Associated Press on Sunday.

Investigators found the mask after they finished clearing the home of booby traps and ammunition, a law enforcement official close to the investigation said Sunday on condition of anonymity because he was not authorized to speak to the news media.

James Eagan Holmes, 24,Â has been held in solitary confinement at an Arapahoe County detention facility but will be moved Monday to a next-door courtroom for a 9:30 a.m. MDT hearing, where the charges against him of suspicion of first degree murder will be read.

Holmes was arrested Friday after authorities say he set off gas canisters and shot unsuspecting movie-goers in an attack that killed 12 people and injured dozens of others.

Shocked Aurora vows, 'We will not forget' victims of theater shooting rampage

Holmes has been assigned a public defender and Aurora Police Chief Dan Oates said that the 24-year-old former doctoral student has "lawyered up."

"He's not talking to us," the chief added.

On a day of prayer and reflection, Aurora, Colo. comes together after being torn apart by the shooting rampage early Friday morning. NBC's Miguel Almaguer reports.

Holmes has been held without bond at the lockup in Centennial, Colo., about 13 miles from the Aurora theater. He will be advised of the charges against him, and he could also face additional counts of aggravated assault and weapons violations.

'I refuse to say his name'
Arapahoe County District Attorney Carol Chambers will decide whether to seek the death penalty for Holmes. She has prosecuted two of the three inmates on Colorado's death row. Chambers may not announce her plan at the hearing.

Oates said it could take months to determine a motive and police are working with FBI behavioral analysts.

On Sunday, President Barack Obama traveled to Aurora, a Denver suburb of 325,000, to offer comfort to families of the victims. He told them their loved ones would be remembered long after the justice system was done with the killer.

The dead included war veterans, an aspiring sportscaster who had barely escaped a shooting in a Toronto mall earlier this summer, and a six-year-old girl.

Many in Aurora have vowed to deny Holmes the publicity they believe he craves by not uttering his name.

Aurora pastor: 'The storms of life happen to all of us'

"I refuse to say his name. In my house we're just going to call him Suspect A," Colorado Governor John Hickenlooper told a memorial on the steps of the municipal center in the Denver suburb on Sunday night. He captured a spirit of defiance voiced by citizens as well as religious and political leaders.

Among the 12 who died early Friday at a movie theater in Aurora, Colo. were fathers, mothers, a little girl â€" even heroes. NBC's Kristen Dahlgren reports.

Grad school status used to get hazardous materials?
On Sunday, officials at the University of Colorado Anschutz Medical Campus were looking into whether Holmes used his position in a graduate program to collect hazardous materials, but school officials weren't saying whether they knew he was anything more than a hard-working student.

Police have said that Holmes began buying guns at Denver-area stores nearly two months before Friday's shooting and that he received at least 50 packages in four months at his home and at school.

Six-year-old girl, sailor, aspiring broadcaster among Colorado shooting victims

While the university disclosed that it was cooperating with police in the case, that disclosure was one of the few it has made three days after the massacre. It remained unclear whether Holmes' professors and other students at his 35-student Ph.D. program noticed anything unusual about his behavior.

His reasons for quitting the program in June, just a year into the five- to seven-year program, also remained a mystery.

As detectives pored over evidence from the home of Aurora shooting suspect James Holmes, it became clear how complicated the investigation might be. NBC's Mike Taibbi reports.

Holmes recently took an intense, three-part oral exam that marks the end of the first year. Those who do well continue with their studies and shift to full-time research, while those who don't do well meet with advisers and discuss their options, including retaking the exam. University officials would not say if he passed, citing privacy concerns.

The university said Holmes gave no reason for his withdrawal, a decision he made in June.

Holmes was not allowed access from the institution after his withdrawal, which was "standard operating procedure" because he was no longer affiliated with the school, said Jacque Montgomery, a spokeswoman for the medical school. Holmes had no contact with university police, she said.

The university declined to release any details of his academic record, citing privacy concerns, and at least two dozen professors and other staff declined to speak with The Associated Press. Some said they were instructed not to talk publicly about Holmes in a blanket email sent to university employees.

The gun debate rages in the aftermath of the Aurora shooting -- advocates say President Obama has done little to curb gun violence. Meanwhile, Mitt Romney says he opposes new restrictions. NBC's Mike Viqueira reports.

The Associated Press and Reuters contributed to this report.

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