UPDATE 2:41 p.m.:

The FBI is now investigating the attack as "an act of terrorism," the Associated Press reports. David Bowdich, assistant director of the FBI's Los Angeles office, also confirmed that Malik and Farook destroyed potential evidence in the form of two cell phones.​

See original story below.

Tashfeen Malik, the woman who helped her husband Syed Farook fatally shoot 14 people at the Inland Regional Center in San Bernardino on Wednesday, reportedly pledged allegiance to ISIS in a since-removed Facebook post. The post allegedly expressed support for Abu Bakr al-Baghdadi and was posted "just before the attack," according to NBC News. Though the post isn't being considered as indicative of mutual support or direct communication with ISIS, authorities are still naming a specific motive.

"At this point we believe they were more self-radicalized and inspired by the group than actually told to do the shooting," an anonymous official clarified to the New York Times, adding that the couple had also taken "several steps" to wipe their digital footprints in the days leading up to the San Bernardino attack. This behavior, according to officials, leads investigators to believe the act was premeditated. Though the post has been removed from Facebook, officials were able to confirm that it was made from an account "with a different name," CNN says.

Both Farook and Malik, who were married, were ultimately killed by authorities during a violent shootout involving 21 officers. A pipe bomb was later discovered at the scene, in addition to 12 more devices and "more than 4,500 rounds" of ammunition recovered during a home search. The massacre marks the 355th mass shooting in the United States in 2015 alone.