The dark sport utility vehicle with tinted windows traced a haphazard path through the streets of San Bernardino.
The couple inside had just killed 14 people but seemed in no hurry to flee the city. For several hours, they meandered through an L-shaped area defined by the 215 and 10 freeways, often passing into the frame of traffic cameras and surveillance footage.
They briefly pulled over near Seccombe Lake and in a parking lot near the Inland Regional Center, where they had opened fire at a holiday party that morning.
The Dec. 2 trek of Syed Rizwan Farook and his wife, Tashfeen Malik, was pieced together by federal authorities and provides new details about their final hours before they were killed in a firefight with authorities.
Investigators say they aren't sure why Farook and Malik decided to stay in the area. But one law enforcement source said officials believe the couple might have been trying to remotely detonate a pipe bomb that Farook had left at the center.
Agents said Tuesday they have yet to figure out what the couple were doing for a critical chunk of time — 12:59 p.m to 1:17 p.m. When Farook and Malik resurfaced, they were a mile from the center, which at that time was flooded with paramedics, police, reporters and family members frantically searching for loved ones.
"We're missing that 18 minutes," said David Bowdich, assistant director in charge of the FBI's L.A. office. "We're dark."
Filling in that missing link, he said, would help investigators determine whether Farook and Malik stopped at any homes or businesses or met with anyone else after the attack.
He said the couple's route involved "a lot of zigzagging around, going back and forth on the highway. There is no rhyme or reason to it that we can find yet."
The FBI has said the couple — who carried out what authorities call the deadliest terrorist attack on U.S. soil since Sept. 11, 2001, — appeared to have embraced radical Islamic teachings and had been radicalized "for quite some time."
During a news conference Tuesday, Bowdich said the investigation had turned up no evidence that the attack was orchestrated from abroad.
"This seems to be an inspired terrorist act," he said.
Bowdich also gave the most detailed timeline to date for how the couple spent the day of the attack.
Farook left his Redlands home at 8:37 a.m. and arrived at the Inland Regional Center 10 minutes later, carrying a bag containing a pipe bomb.
An FBI affidavit said the device was made of three galvanized steel pipes and smokeless powder, and was attached to a remote-control toy car. The bomb was "armed and ready to detonate." Agents found a remote control for a toy car in the couple's SUV, the affidavit said.
A federal law enforcement source who requested anonymity because the investigation is still in progress said it was possible the couple were unable to detonate the device because they were out of range or because sprinklers that had gone off in the regional center interfered with the explosives.
Farook spent about two hours at the center the morning of the shooting, Bowdich said, socializing with coworkers gathered for a holiday event. Authorities haven't found any evidence to support suggestions that a workplace dispute led to the shooting, Bowdich said, adding that Farook's demeanor was normal that morning and that photos taken of him inside the facility during the event didn't show anything out of the ordinary.
Farook left the event at 10:37 a.m., leaving the bag behind. Authorities still don't know where Malik was before her husband left the facility. It's possible, they say, that she went with her husband to the center that morning and waited in the SUV.
The FBI declined to say where Farook went after he left. But the law enforcement official said investigators do not believe Farook would have had time to go back to his Redlands home before the attack.
When Farook returned to the event at 10:56 a.m., he was with his wife. The couple had several weapons, including two military-style rifles.
The shooting lasted about five minutes. The investigation shows that both rifles used by the couple were fired inside the conference room where the victims were shot, the law enforcement source said.
After fleeing in the SUV, the couple drove through parts of San Bernardino and Redlands — pausing at the lake about 11:45 a.m. Bowdich said a search of the lake hadn't turned up anything of value to the investigation.
Authorities were able to track the couple's whereabouts until just before 1 p.m., when Farook and Malik were near the intersection of the 215 and 10 freeways, FBI spokeswoman Laura Eimiller said. Eighteen minutes later, the couple's SUV was at the Waterman Avenue exit on the 10 Freeway.
A few minutes before 3 p.m., authorities spotted the SUV while conducting surveillance at their Redlands home. After a brief pursuit, Farook and Malik died in a gun battle with law enforcement officers.
San Bernardino County Sheriff John McMahon said the attack would probably cost the county about $4 million, including overtime costs for police and emergency personnel as well as lost salaries and business for others affected. San Bernardino police Chief Jarrod Burguan said his department spent $350,000 in overtime alone in responding to the killings.
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