Story highlights

A couple stormed a party in Southern California and shot 14 people to death

The FBI said it is treating the attack like a terror investigation

CNN —  

Days after a Southern California couple shot 14 people to death, federal authorities are treating the massacre as an act of terrorism.

But it’s unclear what drove the couple to storm a holiday party in San Bernardino and spray the husband’s coworkers with bullets.

Tashfeen Malik and her husband, Syed Rizwan Farook, injured 21 others in the deadly attack Wednesday – before authorities gunned them down in a shootout the same day.

As more details come in about the attackers, so do the questions.

Here’s what we know – and don’t know – about the massacre:

Was it a terror attack?

Shortly after the attacks, officials shied away from implying the massacre had any links to terror.

But the narrative changed Friday, when the FBI took over the investigation from San Bernardino authorities. The agency said it was treating the attack as an “act of terrorism.”

There was “evidence … of extreme planning” of the killings, said David Bowdich, an assistant FBI director.

And while the mass shooting may have been inspired by ISIS, a law enforcement official said, there’s no indication the terror group directed or ordered the attack.

“This is looking more and more like self-radicalization,” a law enforcement official said on condition of anonymity.

The couple did not have any trouble with the law, nor were they on any list of potentially radicalized people.

Relatives had no idea that the couple held radical views, according to family lawyers.

Was a religious dispute to blame?

Authorities have said in addition to terrorism, workplace disputes could be a possible motive. Or a combination of the two could have fueled the attack.

Syed Rizwan Farook and Tashfeen Malik
FBI/GETTY IMAGES
Syed Rizwan Farook and Tashfeen Malik

With every suggested motive are lingering questions.

If the attack was a result of workplace dispute, why did the killers have weapons in the home they lived in with their 6-month-old baby?

Shortly after the massacre, authorities said they searched their house and found pipe bombs, thousands of rounds of ammunition and more guns.

If it was terrorism, why did they choose to massacre his coworkers? Why did they pick a mundane, low-profile building that has no symbolic or historical significance?

Has ISIS claimed responsibility?

No.

Yet the terror group has hailed the couple, describing them as “supporters.”

But for a group quick to claim credit and thump its chest after high-profile attacks, it was notable that ISIS did not say the couple were members or that it was responsible.

When claiming responsibility for other terrorist attacks, ISIS normally hails attackers as “knights” or “soldiers.” This time, it stuck to “supporters,” using its official radio station to say it hopes God will “accept them as martyrs.”

“What they’re calling these two are supporters, which is kind of a lesser level,” indicating it might not have had direct contact with the couple, said Rick Francona, a CNN military analyst and a former intelligence officer.

That said, the group has made general, vague calls urging sympathizers to carry out attacks on their own.

Did the two have ties to ISIS?

Tashfeen Malik and her husband, Syed Rizwan Farook, sprayed bullets at Farook’s co-workers at a holiday party for the environmental health department in San Bernardino before being gunned down in a shootout with authorities the same day.

Female shooter Tashfeen Malik made a public declaration of loyalty to ISIS while the attack was underway. Three U.S. officials familiar with the investigation said she posted to Facebook a pledge of allegiance to ISIS leader Abu Bakr al-Baghdadi.

Facebook said it took the post down because it violated community standards that prohibit the promotion of terrorism or the glorification of violence. It declined to go into details about the nature of the post.

The couple’s motivation for the attack is a key focus for investigators. But ISIS’ acknowledgment of Malik and Farook as supporters doesn’t mean they were members or that someone from the group ordered it, said retired Air Force Lt. Col. Rick Francona, a CNN military analyst and a former intelligence officer.

On Saturday morning, officials briefing President Barack Obama about the investigation told him that they had “no indication that the killers were part of an organized group or a broader terrorist cell,” the White House said.

Did they travel to the Middle East?

Farook, 28, was born in Illinois and raised in California. He traveled twice to Saudi Arabia – first in 2013 for the Hajj, the annual pilgrimage to Mecca that Muslims are required to make at least once in their lifetimes, and then then again to marry Malik, whom he’d met through an online dating service, said Farook family attorney Mohammad Abuershaid.

Farook was born in Illinois to Pakistani parents and raised in California. He made two trips to Saudi Arabia.

The first visit was in 2013 for the Hajj, the annual pilgrimage to Mecca that Muslims are required to make at least once in their lifetimes.

The second time, he went to marry Malik, whom he’d met through an online dating service, family attorney Mohammad Abuershaid said.

The FBI said he went to Pakistan as well, but the family attorneys denied that.

Malik was born and raised in Pakistan and moved to Saudi Arabia around the age of 18 or 20, Abuershaid said.

She came to the United States on a fiancée visa and became a legal permanent resident.

A federal official said Farook has “overseas communications and associations,” but it’s not yet clear how relevant they are to the shootings. “We don’t know yet what they mean,” the official said.

“We don’t know yet what they mean,” the official said.

A look inside the killers’ home

Bowdich called this an attempt to destroy “digital fingerprints.”

The FBI inventoried what they found and returned custody of the home to the landlord. The inventory listed parts for guns, about 5,000 rounds of ammunition, tools, gun boxes, holsters, electronics, Christmas lights, a thumb drive, a laptop and a cellphone with a SIM card missing.

CNN’s Jason Hanna, Greg Botelho, Jim Sciutto, Pamela Brown and Barbara Starr contributed to this report.