How long were they radicalized?
The FBI on Monday said "for quite some time," but declined to be more specific.
Officials have said the couple appears of have planned the attack for at least a few months, amassing weapons, ammunition and explosives. As of now, investigators say they have no evidence they were aided by others in the area. But they stress the investigation is still in the early stages.
"We are attempting to expand that investigation out and build it and build a picture of each person, the timeline and ultimately the crimes they committed," said David Bowdich, assistant director in charge of the FBI's Los Angeles office. "That takes time. We are in Day 5."
Did Malik influence Farook?
Because of Malik's connections to Pakistan, some have speculated that she was the driving force behind the attack. Farook was born in America. But Bowdich said both were radicalized. Sources have told The Times they are looking into whether Farook made connections on the Internet to Islamic terrorist figures.
Federal investigators are trying to determine if Farook was influenced by Mohamed Abdullahi Hassan, a former Minneapolis resident known as "Mujahid Miski" who became a recruiter for Islamic State and is alleged to have encouraged the attempted attack on a cartoon contest in Garland, Texas, earlier this year. The U.S. State Department said Monday that Hassan turned himself in to authorities in Somalia, where he had been hiding.
FBI officials have said that Farook had "some contact" with someone known to the FBI in this country and also reached out digitally to at least two members of foreign terror groups, including one in Somalia, said a federal law enforcement official who is unauthorized to speak publicly on the matter.
What does it mean when officials say the couple might have been "self-radicalized?"
THis means that someone comes to hold extreme political beliefs -- in this case becoming a terrorist -- without being part of a larger terrorist organization.
Where does the investigation stand now?
Scrubbing the backgrounds of the couple — who were killed in a shootout with police hours after their rampage — has been an international effort, with cooperation from foreign governments. In Pakistan, where Malik attended college and Farook's parents were born, the interior minister announced that an inquiry into the shooters' backgrounds had been launched. Investigators were also looking to sources in Saudi Arabia, where Malik lived as a child.
Who is Enrique Marquez and how does he fit into the investigation?
John D'Angelo of the Bureau of Alcohol, Tobacco, Firearms and Explosives said five guns were recovered from the shootout scene and the couple's rented two-story townhouse. Farook had legally purchased a Savage Arms .22 rifle, a Llama 9mm handgun and a Springfield Armory 9mm handgun between 2007 and 2012, D'Angelo said.
Acquaintance Enrique Marquez had given the couple the semiautomatic Smith & Wesson M&P15 and .223-caliber DPMS A-15 rifles, authorities said.
Until a few months ago, Farook and Malik lived in Riverside, next door to Marquez. Farook, observed as quiet and withdrawn, struck up a friendship with Marquez, who shared a similar interest in tinkering with cars, a neighbor recalled.
Federal authorities interviewed Marquez over the weekend, and a law enforcement official familiar with the investigation said the weapons he gave to Farook were legally purchased in 2011 and 2012. There is no paperwork of them being transferred to Farook, he said.
On Sunday, the FBI seized items from Marquez's home after having spent several hours there the day before, according to neighbors. There was no indication at the time that Marquez had any knowledge of the plot, a source said.
What about the couple's 6-month-old baby?
Farook's sister and mother hope to gain custody of the baby, the Council on American-Islamic Relations said in a statement. The organization said it is working to place the baby with a Muslim family as it remains in child protective services. A follow-up custody hearing has been scheduled for January.
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