The FBI has now taken over the investigation, calling the shooting rampage an act of terrorism.
A Facebook executive told the Associated Press Friday: Malik used an alias account to post her allegiance to the Islamic State, just moments after the attack began. The account has been removed from public viewing.
PHOTOS: Inside Redlands home of San Bernardino shooting suspects
Investigators took items from the couple's home in the nearby city of Redlands. They also found two cellphones, smashed, but salvageable near the couple's home.
"We do continue to exploit the data from those cellphones. We do hope that the digital fingerprints that were left by these two individuals will take us toward their motivation," said FBI assistant director David Bowdich.
The landlord of the couple's home opened it up to the media and some neighbors Friday. Anyone looking for a reason why the suspected shooters may have killed didn't get an answer while walking inside the Redlands home the couple rented since May.
"I opened it up because I needed to take pictures of the damage myself for insurance purposes," said the couple's landlord.
What the landlord found was signs of a police raid, but otherwise, kids items and evidence of the life of a family that looked as if they intended to come back.
"It seemed like they were regular human beings and that's why it's amazing," a neighbor said.
Inside the home was a copy of the Koran, some receipts from Home Depot with the name of the shooter in this case. What was not in the home was the massive amount of ammunition and a dozen bombs that was collected earlier by the FBI.
"Wow, making bombs in my backyard practically, that's crazy," said one neighbor.
Farook and Malik weren't being tracked by the FBI. Authorities say the couple met on an online dating site. Farook, an American, brought Malik of Pakistan and Saudi Arabia, to the United States on a spousal visa. So far, there's no proof that anyone was directing them from abroad.
It's unclear who called the shots in the couple's home.
"I don't know the answer whether she influenced him or not as a husband myself we all influenced but I don't know," Bowditch said.
The couple's six-month baby is currently in protective custody. A family attorney says the baby may be going home with family member as early as next week.
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