FBI Needs Help Solving Mystery Of 'Critical' 18-Minute Gap In San Bernardino Shooting Timeline

LOS ANGELES -- Investigators are asking the public to help piece together where the San Bernardino attackers were during an 18-minute gap in their known movements on the day they massacred 14 people, the FBI announced Tuesday. 

Law enforcement officials have accounted for three hours and 42 minutes of the movements of Syed Rizwan Farook and his wife, Tashfeen Malik, from when the couple opened fire inside the Inland Regional Center on Dec. 2 until they were both killed by police later that day following a chase. But investigators have a missing section in their timeline between 12:59 p.m. and 1:17 p.m. that day, and they hope that the public can help fill it out by providing cell phone video, surveillance footage or other witness accounts of the assailants.

"That 18 minutes is critical," FBI special agent David Bowdich said during Tuesday's press conference. "It's possible they stopped at a storage area, a residence or a business. We just don't know. It very well may not be an important fact, but we just don't know.

Bowdich gave reporters an L-shaped map that defines the region in which Farook and Malik moved about in their timeline. 

"There was a lot of zig-zagging around, no rhyme or reason for that yet," Bowdich said, "and maybe that 18 minutes solves that."

While the FBI has said that the couple had been radicalized for some time before they met,  and while the couple supported terrorist groups like the self-proclaimed Islamic State , on Tuesday Bowdich made clear that the attack appears to be an "inspired terrorist act" and not a foreign-directed one.

Bowdich also said that early reports that some kind of workplace dispute took place in the moments before the shooting do not line up with what the investigation is finding.

"We do not see any indication of a fight or argument with Syed in the venue," Bowdich said. "We found no legitimate accounts of that. [His] demeanor seemed to be OK, there are photographs of him inside the venue, seemed to be OK."

So far, the FBI says it has has conducted 550 interviews, collected 500 pieces of evidence and executed 29 warrants in its investigation into the massacre. 

Last month federal authorities released a detailed criminal complaint against 24-year-old Enrique Marquez, the first person charged in the attack. It alleges that Marquez, who was once close friends with Farook, plotted terrorist attacks with him in Southern California for years, but the two had drifted apart by the time Farook and Malik attacked the group of Farook's coworkers in San Bernardino.

Anyone who has information about the San Bernardino shooters, or the gap in law enforcement's timeline, should contact the FBI at 1-800-CALL-FBI.

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