San Bernardino shooting: 'What is the motivation for this?'

[Lacoste]

They left no manifesto. The hard drive was gone from their computer. And their new cell phones were apparently smashed.

Syed Rizwan Farook and his wife Tashfeen Malik did their best to fly under the radar. Neither got into trouble with the law. And neither one was on any list of potentially radicalized people.
So, a day after one of the deadliest mass shooting in the United States, authorities are still left wondering what motivated the couple to mow down dozens of people at a holiday luncheon in San Bernardino, California. Fourteen people died and 21 were injured.

 
Officials say part of the reason may have been Farook's apparent radicalization. Part of it may have stemmed from workplace tensions.
But nothing concrete has surfaced.

"It would be irresponsible and premature for me to call this terrorism," said FBI official David Bodwich on Thursday. "The FBI defines terrorism very specifically, and that is the big question for us: What is the motivation for this?"
 

Was he radicalized?
 
One avenue investigators are exploring are Farook's communications with at least one person who was being investigated for possible terror connections. Some were by phone, some conducted on social media.
"These appear to be soft connections," an official said, meaning they were not frequent contacts. Farook's last communication with the contacts was months ago.
The FBI wants to interview some of them to learn more about their conversations with Farook.
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.
There are no clear ties to overseas terrorists groups so far.