San Bernardino shooting: What we know about the suspects

While police are still piecing together what triggered today’s mass shooting in San Bernardino, there are early reports the deadly incident was triggered by a fight at a Christmas party.

The Los Angeles Times and NBC News are reporting that one of the gunmen has been positively identified by police as Syed Farook, an American citizen.

NBC has also reported that Mr Farook’s brother is believed to be a suspect in the shooting.

A person by the name of Syed R Farook is employed by the San Bernardino County Health department as an environmental health specialist, according to local media.

The identity of the deceased female suspect remain unknown.

Police are also investigating reports the assailants opened fire at a Christmas party being held for the Inland Regional Centre following an argument.

Senior police reportedly believe a man involved in the argument returned with one or two armed companions and opened fire.

During a news briefing, San Bernardino Police Chief Jarrod Burguan said information surrounding the attack was still "preliminary".

“We have no information at this point to indicate that this is terrorist related, in the traditional sense that people may be thinking,” Burguan said.

“Obviously, at a minimum, we have a domestic terrorist-type situation that occurred here.”