"We have the evidence of a deliberative process to commit this assault, and we have the evidence of a deliberative process in his mind to attack whoever opened the door of his apartment."
Colorado Gov. John Hickenlooper told CNN's "State of the Union" Sunday that he spent a day going from hospital to hospital, talking with survivors.
He concluded that Holmes was a person who wanted to terrorize and instill fear in people's lives, but said he can't conceive of a motive.
"This is a deeply troubled, twisted, delusional person," he said.
Police gained access Saturday to Holmes' apartment after intentionally detonating two rigged explosives.
Technicians, with the help of a robot, worked to handle traps, wires and possible explosive and incendiary devices, Jim Yacone, a special agent with the FBI, told reporters Saturday.
The operation proceeded with an eye toward preserving evidence, all of which will be sent to an FBI lab in Quantico, Virginia, said Yacone.
Hundreds of residents were evacuated from five buildings, including the modest, three-story brick building where Holmes told police he had rigged his top-floor, one-bedroom apartment with explosives. All occupants except those who live in the suspect's building were allowed to return home Saturday night, said police.
While the threat to the apartment building Holmes lived was eliminated Saturday, Oates said the residences were being kept out at least until Sunday as investigators work "to preserve evidence."
By early Sunday morning, at least 26 people remained hospitalized -- nine in critical condition -- in five area hospitals.
Aurora's residents, meanwhile, were grappling with the aftermath of the carnage.
President Obama was due to meet with the injured and the families of those killed Sunday night in Aurora, where the city was planning a vigil that was expected to draw various public officials.
Oates said the Century 16 multiplex would remain shuttered at least until Wednesday to give police time to complete the investigation inside and allow the suspect's defense team access by Tuesday.
Holmes, who is being held in the Arapahoe County Jail, is scheduled to appear in court on Monday morning. The court file was sealed, according to a court order.
Investigators have said little about what may have led the suspect to open fire during a screening of the new Batman movie, "The Dark Knight Rises".
Witnesses described the gunman as wearing a gas mask that concealed much of his face and head.
Holmes' hair was dyed red, and he told police when he was arrested in the rear parking lot of the theater minutes after the rampage that he was "the Joker", according to a federal law enforcement source with knowledge of the investigation. The source was not authorized to release details to the media.
The Joker has long been a fixture in Batman comics and was famously portrayed by Heath Ledger in 2008's "The Dark Knight," the predecessor to "The Dark Knight Rises."
Oates has declined to release details about Holmes' appearance other than to describe what he was wearing: a ballistic helmet and protective gear for his legs, throat and groin, black gloves and a gas mask.
He also said he would not release the booking photo "for investigative reasons."
Intellpuke: You can read this article by CNN Correspondent Chelsea J. Carter in context here: edition.cnn.com/2012/07/22/justice/colorado-theater-shooting/index.html?hpt=hp_t1
CNN's Tom Watkins, Dana Ford, Carol Cratty, Ed Lavandera, Susan Candiotti, Joe Sutton, Mike Brooks, Sarah Aarthun and Jim Spellman contributed reporting to this news article.