The attack began on Wednesday morning, at an office holiday party in the Inland Regional Center in San Bernardino. The center provides social services to residents with developmental disabilities, but the shooting was focused on an office party for San Bernardino County staff.
As a county employee, Farook was at the party. At some point he left in anger, Burguan says.
He returned with Malik.
Both were dressed in "tactical gear" (including load-bearing vests, but not ballistic or bulletproof vests) and carrying .223-caliber assault-style rifles and semiautomatic handguns, police say.
The weapons used in the shooting were legally purchased, Burguan says: The handguns were purchased by Farook, and authorities are still investigating who purchased the rifles.
Farook and Malik entered the Inland Regional Center and fired between 65 and 75 rifle rounds, Burguan said Thursday.
A bomb — three explosive devices, linked to a remote control car and placed inside a bag — was also discovered at the shooting site, but it failed to go off, Burguan said.