Dec. 05--One of the shooters in the San Bernardino massacre pledged allegiance to an Islamic State leader on Facebook about the same time she and her husband opened fire at a holiday party, killing 14 people, according to a source with knowledge of the matter.
The source spoke on the condition of anonymity because he or she was not authorized to speak.
The source said Facebook discovered the post from Tashfeen Malik after searching its user database for the shooters' names.
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A Facebook spokesman declined to comment on details of the post, including the user's name, the time it went live or what it said, citing company policy about posts that violate its terms of use.
But the spokesman said the company regularly removes posts that voice support for or glorify either terrorists or terrorist organizations.
The FBI formally announced it was investigating the shooting rampage Wednesday at the Inland Regional Center as an act of terrorism.
FBI Director James Comey said that the assailants, Malik and her husband, Syed Rizwan Farook, showed signs of "radicalization" but there was no evidence they were part of a larger terror network.
