By Marisol Bello, Kevin Johnson, Elizabeth Weise and Trevor Hughes, USA TODAY
AURORA, Colo. (USA TODAY)- Signs of James Eagan Holmes' descent from a quiet but brilliant neuroscience student to a suspect in a mass shooting were on display in his 800-square-foot apartment, where police say they found a maze of explosive devices, trip wires, chemicals and a Batman mask.
It is unclear what might have motivated Holmes, 24, to allegedly don head-to-toe black body armor and methodically open fire on a sold-out showing of the movie TheDark Knight Rises in suburban Denver, killing 12 people and injuring 58.
Authorities are sifting through the finds in his Aurora, Colo., apartment, hoping to shed light on the mind, motive and modus operandi of the suspect.
As Holmes sits in the Arapahoe County jail awaiting his first court appearance on Monday, residents in this suburban Denver community of 330,000 spent Sunday praying at church and comforting each other at an evening vigil.
Pastor Mitch Hamilton says Americans are getting uncomfortably familiar with attacks on our own soil.
"Such horrific tragedy used to always occur somewhere else," says the pastor of the Mississippi Avenue Baptist Church, about a mile from the shooting site. "Now, it's occurring here."
For Hamilton, Friday's horror was driven home when a young woman walked into the church and asked a simple question: "Why did my cousin die?"
Why? The question - or some form of it - is resonating in the stricken city and across the country. Why did a gunman do this? Why in a movie theater, which has been a cultural sanctuary where moviegoers seek to escape reality. It's the strained query that has echoed across the nation's grieving landscape after senseless shootings at Columbine, Virginia Tech and Fort Hood.
The answer, when and if it comes, is rarely sufficient.
The key question in the Aurora case: How did the skinny teen with the easy smile in his San Diego high school yearbook photo, who kept to himself and loved science, unravel into the man police say attacked the theater and booby-trapped his apartment to commit more mayhem and take more lives?
"I assume something must have snapped," says Jerry Borgie, senior pastor at Peñasquitos Lutheran Church, which Holmes' family attends in San Diego. "This is just so absurd and so out of character in my understanding of this young man and the way he lived his life. He wasn't just some shiftless kid who had no ideas. He had some goals. He had a purpose. He worked hard."
Police spent most of the weekend at Holmes' apartment defusing the maze of booby-traps.
A federal law enforcement official, who asked not to be identified because he is not authorized to comment publicly, said among the items recovered from Holmes' apartment was a computer - which authorities hope could reveal a motive and plans for the assault - a Batman mask and other Batman paraphernalia.
A deadly apartment
Yet simply accessing Holmes' apartment took authorities the better part of two days. Incendiary devices arrayed inside included 10 gallons of gasoline, probably meant to serve as an accelerant to any fire caused by an explosion, the official said. The devices included about 30 aerial shells commonly used in commercial fireworks.
The official said the shells had been cannibalized, reconstructed and set up in the living room, where a stream of wires connected them to a "control box" in the unit's kitchen. Bomb technicians disabled the box Saturday.
Had the devices detonated as planned, the official said, the explosion and gasoline would have created a "fireball" that most likely would have consumed the apartment and perhaps much of the building's top floor.
"This apartment was designed to kill," Aurora Police Chief Dan Oates said. He said Holmes had received a "high volume" of deliveries of materials and ammunition. Over the course of four months, he said, the suspect had at least 50 packages arriving to his home and the university.
The University of Colorado is helping authorities determine whether packages arrived for Holmes when he was a student there, spokeswoman Jacque Montgomery said.
Holmes dropped out of the school in June. The university has not said why he left the school.
Holmes gave no indication to anyone of what he was doing, said Aurora Mayor Steve Hogan, who told ABC News that the suspect planned the attack for months but apparently hid the scheme from friends.
"This guy was smart," Hogan said. "He had friends who went drinking with him that night, and no indication. But this is something he had planned for months."
Forensic psychiatrists and mental health experts say that as authorities piece together the evidence and look into Holmes' behavior, there is a high likelihood that they'll start to see clues that his mind was unraveling.
"I don't know if this guy was mentally ill or if he was the epitome of evil," says Steven Pitt, a forensic psychiatrist who consulted on the 1999 Columbine shooting just miles from Aurora. "But I can promise you that as additional information comes out, a picture will be painted of a very disturbed individual even before he committed this act."
In some cases, mental health experts say, warning signs appear in a subject's fascination with guns or even a direct threat to kill people. A person might even isolate himself or appear delusional, they say. But experts emphasize that pinpointing when a person will explode in a wave of violence is a whole other matter.
Millions of shy or solitary people don't take up weapons and murder people in movie theaters, just as being decked out in all black isn't an indication someone is likely to commit mayhem, Detroit psychiatrist Vasilis Pozios says.
"We're just not good at predicting who does this," says Pozios, who studies violence risk assessment.
But people who had run-ins with Holmes in the days and weeks leading up to the massacre say he acted a bit strange.
Glenn Rotkovich, owner of the Lead Valley gun range in Aurora, said Holmes tried to become a member of his private gun range on June 25. Rotkovich was hesitant to let him join after he tried to reach Holmes several times at home, and all he heard was a "creepy, weird, guttural" voice mail. The message didn't make any sense, Rotkovich said.
"It was bizarre and intentional," he said.
While other people his age are active in social media, Holmes seems to have little online presence. He has no Twitter or Facebook profiles.
Two federal law enforcement officials, who spoke on the condition of anonymity because they are not authorized to speak publicly, say Holmes had been on the dating site Adult Friend Finder, where a post showed a photo of a man with dyed red-orange hair who appears to be Holmes. Ominously, he asks on the page, "Will you visit me in prison?"
'I was sick, really sick'
In Rancho Peñasquitos, a community of picturesque hacienda-style homes surrounded by hills and canyons outside San Diego where Holmes grew up, residents have a hard time squaring the shy teen who didn't call attention to himself with the image of Holmes depicted by police as a calculating killer. Those who knew him remember a polite young man who kept to himself and excelled academically.
Borgie, the pastor, says it never occurred to him that the man accused of killing 12 in a hail of bullets was the young man he'd known for a decade.
"I didn't make the connection," he said. Only when Borgie got home from a trip did he realize that the Holmes being held in Colorado was the same Holmes he knew. "I was sick, really sick," he said, noting that Holmes didn't stand out, other than being "maybe a little on the shy side."
Holmes, who graduated with high honors with a bachelor of science degree in neuroscience from the University of California-Riverside, was raised in a math and science household. His mother, Arlene, has been licensed as a registered nurse for more than 30 years. His father, Robert, is a mathematician who develops statistical models for financial services, specifically looking at fraud.
Arlene Holmes is "the spiritual leader in the family," Borgie says. "She sets a good example. She's kind of a quiet person who will do what needs to be done because she thinks it needs to be done. And if she gets credit for it, fine, and if she doesn't, that's fine, too. A special lady."
At a service Sunday in San Diego, parishioners offered prayers for the Holmes family and the family and friends of the victims in Colorado. In the church's fellowship hall, two large pieces of butcher paper had been hung, one for members to write prayers for the Holmes family and one for the victims and their families in Colorado.
William Parkman and his wife, Porsche, both 19, knew Holmes because they went to high school with his sister, Chris. William Parkman marveled at how Holmes had gone from a proud example of a successful local graduate to one of the most hated people in the country.
"The news reports you hear about him, it's as if people are talking about one person in San Diego and one in Colorado," Parkman said. "Who he is now is not who he was in San Diego."