US police identified Syed Rizwan Farook (28) and Tashfeen Malik (27) as suspects after a shooting that killed 14 people in California on Wednesday.
At least 14 people were killed and 17 others wounded in a shooting at a social services agency in San Bernardino city, southern California in the deadliest shooting since 26 people, mostly children, were killed at a school in Newtown,
Police killed the suspects – a man and a woman - in the hours following the shooting, on a quiet residential street, authorities said.
The motive for the shooting is still unclear and authorities said they are not ruling out any possibilities including workplace violence and terrorism.
San Bernardino Police Chief Jarrod Burguan said Farook and Malik were the only suspects, rejecting earlier reports that there is a third suspect still at large. Burguan added the two were believed to be either married or engaged.
Public records show that Syed Rizwan Farook is a US citizen and worked as an environmental health specialist for San Bernardino County and is listed as residing at an apartment complex where the suspects were found by police. There was no information provided on the background of Malik.
Burguan said that the two suspects fled the scene of the shooting in their car were armed with rifles and handguns and were wearing "assault-style" clothing when confronted by police, in which a police officer was injured.
Burguan also said someone had left the holiday event at the agency, following a dispute prior to the shooting.
"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 had suspicions about the suspects leaving behind an explosive device.
David Bowdich, assistant director of the FBI's Los Angeles office, said authorities were considering terrorism, but were not sure yet.
"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."
A relative of Farook said he had no idea what could have motivated the attack.
"Why would he do that? Why would he do something like this? I have absolutely no idea, I am in shock myself," Farhan Khan, who identifies himself as the brother-in-law of one of the suspects, said in a news conference in Anaheim, California.
The shootings took place during a holiday party on the campus of the Inland Regional Center, an agency for those with developmental disabilities.
US President Barack Obama once again called for tougher gun control measures following the shooting and said a bipartisan effort was necessary "at every level of government" to address mass shootings.
"The one thing we do know is that we have a pattern now of mass shootings in this country that has no parallel anywhere else in the world," he told US media, according to Agence France Presse.
"There are some steps we could take, not to eliminate every one of these mass shootings, but to improve the odds that they don't happen as frequently." he added.