FBI Director James Comey said Wednesday that there is still no evidence that the San Bernardino, Calif., shooters had any contact with a foreign terrorist group like ISIS.

Comey also said Syed Farook and Tashfeen Malik were communicating online in 2013, before meeting in person, and showing signs of radicalization. But he emphasized that these communications were private, saying that investigators have not found public social media postings from that time that would have tipped off authorities to the couple's extremist views.

"Those communications are direct, private messages," Comey said. "So far, in this investigation we have found no evidence of posting on social media by either of them at that period in time and thereafter reflecting their commitment to jihad or to martyrdom."

Authorities say this doesn't include a post in support of an ISIS leader allegedly made by Malik using an alias, according to The Washington Post. The newspaper says:

"These messages are distinct from a note Tashfeen Malik posted on Facebook after the shooting pledging her allegiance to Abu Bakr al-Baghdadi, the emir of the self-proclaimed Islamic State, the militant group that says it has established a caliphate in Syria and Iraq, according to law enforcement officials."

Also on Wednesday, Comey confirmed that theshooting in Chattanooga in July that left five service members dead should indeed be considered as a terrorist attack.

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