Grieving and a search for clues after theater shooting rampage

Colorado Rockies' Jason Giambi, center, looks out to the field as players observe a moment of silence for the victims of the Colorado theater shooting before the start of a baseball game against the San Diego Padres Friday, July 20, 2012, in San Diego. The gunman, identified by police as 24-year-old James Holmes, used a military-style semi-automatic rifle, a shotgun and a pistol, stopping only to reload. At least 12 people were killed and several dozens wounded in one of the deadliest mass shootings in recent U.S. history. (AP Photo/Denis Poroy)