San Bernardino police chief Jarrod Burguan said a third suspect had been detained, but it was unclear whether that person was linked to the shooting, which took place at a center in the city for those with developmental disabilities just before lunch time.
The attack was the latest in a series of mass shootings in the United States, a spiral of violence that has exasperated President Barack Obama, who once again urged Congress to pass tougher gun control measures.
Burguan said authorities were looking at reports that the attack might be linked to a disgruntled employee.
The carnage took place during a holiday event at the Inland Regional Center, a huge facility that employs several hundred people.
“There was some type of dispute or something when somebody left the party, but we have no idea if those are the people that came back,” he said, adding that investigators were looking at the possibility that the suspects had left behind an explosive device.
The attackers were dressed in military-style gear and carried assault weapons as they burst into the auditorium where the killings took place.
David Bowdich, assistant director of the FBI’s Los Angeles office, said authorities were not ruling out terrorism.
“I’m still not willing to say we know that for sure,” he told reporters. “We are definitely making some movements that it is a possibility.”
Investigators in the early evening raided an apartment complex in the nearby town of Redlands, where the suspects were seen before the police chase.
Beyond the 14 dead, the attack also left at least 17 people wounded.
Following the shootout with police, the body of one of the suspects could be seen lying next their bullet-riddled black SUV. The slain suspects were armed with assault rifles and handguns.
Police swarmed the residential neighborhood with officers, guns drawn, going door to door and urging residents to stay in their homes with doors locked.
– Deadliest since Sandy Hook –