'Words are ... inadequate,' Obama tells families of Colorado shooting victims NEW: Thousands gather to pray at a community vigil in Aurora, Colorado NEW: Aurora mayor: "We will reclaim our city in the name of goodness, kindness" (CNN) -- President Barack Obama offered comfort Sunday night to the survivors and the families of the 12 people killed in a mass shooting in Aurora, Colorado, never once mentioning by name the man accused of opening fire in a crowded movie theater. "I confessed to them that words are always inadequate in these kinds of situations, but that my main task was to serve as a representative of the entire country and let them know that we are thinking about them at this moment, and will continue to think about them each and every day," Obama told reporters after the meeting at the University of Colorado Hospital, one of several area medical centers that treated the 58 people wounded in Friday's attack. Though much attention has been paid to the "perpetrator of this evil act," that spotlight will fade, leaving behind just the good memories of those impacted by the tragedy, Obama said. James Holmes, 24, is being held in connection with the shootings early Friday morning and the subsequent discovery of his booby-trapped apartment, which the authorities believe he rigged before leaving for the Century Aurora 16 multiplex. He is scheduled to appear in court on Monday morning. Obama recounted stories told to him by the victims' families and those recovering from injuries. "It reminds you that even in the darkest of days, life continues and people are strong," the president said. Obama spoke before the start of a prayer vigil that brought together state and local officials with thousands of residents. Colorado Gov. John Hickenlooper read the names of those killed. And to each name, the crowd responded: "We will remember." Pastor Robin Holland led a prayer for comfort. City of Aurora, the healing has begun. Your presence here is the step of healing that this nation needs to see. And I am so proud to be a citizen of Aurora, Colorado," he said. Residents lit candles, while balloons, flowers and simple, white crosses collected at a makeshift memorial. It is not this senseless act of violence that marks us as a community. It is the lives and acts of these heroes and the innumerable acts of kindness, love, and care for our neighbors that defines who we are," Aurora Mayor Steve Hogan said at the vigil. We will reclaim our city in the name of goodness, kindness and compassion. Massacre suspect's neighbor: 'I'm counting my lucky stars' The man accused of opening fire inside the theater left a trail of evidence that the police say suggests the shooting was part of a calculated plan that included killing anyone who tried to learn more about him in the aftermath of the attack. The authorities have said little about what they believe was the motive of the accused shooter, though investigators say there is evidence planning was under way for months. Holmes received a high volume of deliveries over the past four months to both his home and work addresses, which the police believe begins to explain how he got his hands on some of the materials used in the attack and those found at his apartment, said Aurora Police Chief Daniel Oates. Gov. 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. Echoing Nowlan's comments, a law enforcement source with direct knowledge of the investigation said Sunday that a semi-automatic rifle used in the killings jammed, apparently because of a problem with the 100-shot magazine feeding it. The military-style AR-15 had a separately purchased drum magazine, which can have trouble feeding bullets into the firing chamber if the gun is fired rapidly, the source told CNN on condition of anonymity. Robots reveal 'unique' setup in suspect's apartment Among the items seized from the apartment were a Batman poster, Batman mask and a computer, according to the law enforcement source. The shootings occurred during a screening of the new Batman movie, "The Dark Knight Rises." Hundreds of residents were evacuated from five buildings, including the modest, three-story brick building where Holmes told the 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. Mears: Aurora survivors, stay strong Gun-control, gun-rights groups prepare for renewed debate CNN's Chelsea J. Carter, Kyung Lah, Carol Cratty, Ed Lavandera, Susan Candiotti, Joe Sutton, Mike Brooks, Sarah Aarthun and Jim Spellman contributed to this report.