Police conducted raids throughout the surrounding neighborhood for hours to look for the shooters. (Photo by Sean Haffey/Getty Images)
SWAT officers stake out in the surrounding streets to search for the suspects. (Photo by Gina Ferazzi/Los Angeles Times via Getty Images)
Law enforcement agents from the surrounding police departments, sheriff's office and federal agencies, went house to house to look for the suspects. (Photo by Patrick T. Fallon/AFP via Getty Images)
Staff from the Inland Regional Center, the facility where the shooting took place, gather to pray and mourn after being evacuated. (Photo by Gina Ferazzi/Los Angeles Times via Getty Images)
Emergency workers evacuate facility staff from the scene of the shooting. (Photo by Mike Nelson/EPA)
Evacuated workers from the Inland Regional Center huddle together across the street. (Photo by Gina Ferazzi/Los Angeles Times via Getty Images)
San Bernardino Police Chief Jerod Burguan speaks at a press conference shortly after the shooting. There "had to be some degree of planning" behind the attack, he said. (Photo via Gina Ferazzi/Los Angeles Times via Getty Images)