Federal law enforcement officials began collecting evidence from the formerly booby-trapped apartment of the suspected Colorado movie gunman on Sunday, NBC News reported.
Authorities took photographs, collected physical and documentary evidence, and began interviewing known associates of the alleged gunman and 80 people who have called a tip line, as they work to uncover a possible motive for the shooting, according to NBC News.
On Saturday, local and federal officials successfully removed explosive materials suspect James Eagan Holmes had left in his apartment before driving to the midnight premiere of "The Dark Knight Rises” in Aurora, Colo., where he allegedly went on an early Friday shooting rampage, killing 12 and wounding 58.
A cache of explosives from the rigged apartment was transported to a remote desert area and detonated, according to NBC News.
Aurora Police Chief Dan Oates told reporters that he believed the rigged apartment targeted the police and was "sure as hell" the suspect intended to kill whoever opened the front door.
"This was certainly challenging," said FBI agent Jim Yacone on Saturday, explaining how officials had to use a robot to disarm a trip wire and bomb.
Yacone also added that "an extensive amount of evidence is in the process of being collected."
Over a four-month period beginning in early May, Holmes began legally purchasing weapons and ammunition, authorities said. Cops confiscated the stockpile at the Century 16 Movie Theaters complex, where Holmes was taken into custody shortly after the mass shooting, NBC News reported.
Holmes has retained legal counsel and was scheduled to appear in Arapahoe District Court Monday at 8:30 a.m. He has not been cooperating with authorities, NBC News reported.
Before moving to Aurora, Holmes was a top-notch college student who seemed to lose his way after leaving home in San Diego to pursue a PhD, friends and associates say.
Holmes ended up at the University of Colorado Medical School’s campus in Aurora, where he reportedly fell behind on his work in recent months and was planning to drop out. In class, he became “strangely quiet” and seemed “socially off,” a faculty member told the Washington Post.
When news of the mass shooting reached Holmes’ hometown, neighbors and former classmates were aghast.
“He was shy and a little quiet, but he was never aggressive or mean,” Sumit Shah, who attended Westview High School with Holmes, told NBC San Diego.
“It’s kind of weird to see him go from the guy I knew to somebody who would kill 12 people and counting.”
Holmes graduated from Westview High School in San Diego in 2006 and back then went by the name Jimmy, classmate Sumit Shah told NBC 4 New York.
“I knew him pretty well, we were friendly,” Shah said. “He was pretty shy, but once he got comfortable with you he was the funniest, smartest guy … He always had something witty to say.”
Shah said he was shocked that his former classmate was "The Dark Knight" shooting suspect.
“The guy I knew in high school, I don’t understand how that could be the same guy,” he said.
Holmes’ uncle, also named James Holmes, said his nephew was a “nerd” and an “unassuming kid.”
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After high school, Holmes attended the University of California at Riverside, where he majored in neuroscience and graduated with honors in 2010. But when he returned home, had had trouble finding work, NBC San Diego reported.
In 2008, Holmes worked as a camp counselor in Los Angeles County that was run by Jewish Big Brothers and Sisters, the group's CEO confirmed to NBC4 on Saturday. The shooting suspect was a cabin counselor at Camp Max Straus during the summer of 2008, Randy Schwab, the CEO of Jewish Big Brothers Big Sisters said in a statement to NBC4.
As cabin counselor, he was responsible for the care and guidance of a group of about 10 children, according to Schwab.
"It is with shock and sorrow that we learned of the incident in Aurora," said Schwab. "Our hearts and prayers go out to all the families and friends of those involved in this horrible tragedy.
"On behalf of Camp Max Straus I want to offer our deepest sympathies and condolences."
In Aurora, Holmes lived in an apartment building reserved for students and faculty of the medical school. On his rental application he reportedly described himself as “quiet and easy going,” the Denver Post reported. A neighbor told the paper that Holmes kept to himself.
Holmes' family in San Diego said in a statement their "hearts go out" to those involved in the tragedy.
Witnesses and police said the gunman had stood at the front of the theater, threw some type of gas then fired into the crowd about 12:30 a.m. MDT.
Moviegoers spoke of their terror as gunfire broke out during a shootout scene. At first some mistook the gunman for a planned part of the show — then "mass chaos" broke out.
"Everybody thought it was a joke or something," witness Skye Kim told Denver's NBC affiliate 9 News.
Benjamin Fernandez, 30, told the Denver Post that he heard a series of explosions. He said that people ran from the theater and there were gunshots as police shouted "get down!"
Fernandez said he saw people falling, including one young girl.
Jordan told the paper that one girl was struck in cheek, others in stomach including a girl who looked to be around 9-years-old.
Jordan said it sounded like firecrackers until someone ran into Theater 8 yelling "they're shooting out here!"
President Barack Obama said in a statement he was "shocked and saddened" by the attack and later offered a moment of silence during a brief campaign appearance in Fort Myers, Fla.
"This morning we woke up to news of a tragedy that reminds us of all the ways that we are united as one American family," Obama said.
Mitt Romney also released a statement after the shooting, saying he and wife Ann Romney were "deeply saddened by the news of the senseless violence."
“Today is a moment to grieve and to remember, to reach out and help, to appreciate our blessings in life,” Romney said later at a campaign appearance in New Hampshire.
Police Chief Oates said officers were working to get a confirmed list of the deceased before beginning the "agonizing process" of meeting with the families of victims. Grief counselors would be on hand through the weekend in Aurora, he added.
On Saturday, a 6-year-old girl was confirmed to have been among the victims of the shooting. Veronica Moser died Friday morning in the shooting rampage, her great-aunt, Annie Dalton, told NBC News. Veronica's mother, Ashley Moser, 25, was shot in the neck and abdomen. She remains paralyzed and hasn't been told of her daughter's death, Dalton said.
Navy officials confirmed on Saturday that Petty Officer Third Class John Larimer, 27, of Crystal Lake, Ill., died from injuries sustained in the mass shooting, NBC News reported. Another sailor was treated for injuries and released at the scene.
"I am incredibly saddened by the loss of Petty Officer John Larimer--he was an outstanding shipmate," said Cmdr. Jeffrey Jakuboski, Larimer's commanding officer. "A valued member of our Navy team, he will be missed by all who knew him. My heart goes out to John's family, friends and loved ones, as well as to all victims of this horrible tragedy."
The first confirmed victim was Jessica Ghawi, an aspiring sportscaster who survived a June 2 mass shooting at a mall in Toronto in which two people were killed and seven others injured. She blogged under the name Jessica Redfield.
Late Friday, the family of Alex Sullivan, 27, said in a statement that he was among the dead, the Denver Post and The Associated Press reported. Photographs taken earlier Friday showed Sullivan's father, Tom, grieving and pleading for information about his son.
The reamining victims, Alexander J. Boik, 18, Jesse E. Childress, 29, Jonathan T. Blunk, 26, Rebecca Ann Wingo, 33, Gordon W. Cowden, 51, Micayla C. Medek, 23 and Alexander C. Teves, 24 were identified by the Arapahoe County Coroner's Office on Saturday afternoon.
Warner Bros., the studio behind "The Dark Knight Rises," said in a statement the company and filmmakers were "deeply saddened to learn about this shocking incident. We extend our sincere sympathies to the families and loved ones of the victims at this tragic time."
Tim Warner, the president and CEO of Cinemark, which owns the Aurora movie theater where the shooting took place, said his prayers were with the victims and their families.
“This is just a huge, huge tragedy. For me personally, this is very heartbreaking. I just feel devastated,” he told NBC DFW.