Keith Hoover (L) and Monica Matryba pray while they hold a photo of friend Jon Blunk, killed while protecting his girlfriend in the Century 16 movie theater shootings last Friday, at a prayer vigil for the victims in Aurora, Colorado July 22, 2012. Thousands of Denver-area residents made a sunset pilgrimage to a sprawling park on Sunday to honor the 12 who died in Colorado shooting and the scores more wounded when a gunman opened fire early Friday in a crowded midnight movie. [Photo/Agencies]

A man holds a sign during a vigil for victims behind the theater where a gunman opened fire on moviegoers in Aurora, Colorado July 22, 2012. Residents of a Denver suburb mourned their dead on Sunday from a shooting rampage by a "demonic" gunman who killed 12 people and wounded 58 after opening fire at a cinema showing the new Batman movie. President Barack Obama headed to Aurora, Colorado, on Sunday to meet families grieving their losses Friday's mass shooting that has stunned the nation and rekindled debate about guns and violence in America. [Photo/Agencies]