FBI Director James Comey says U.S. military strikes have diminished the al Qaeda offshoot Khorasan Group, but the bigger threat faced by the U.S. is now ISIS.
Comey, in an interview with CNN's Wolf Blitzer, used an appearance at the Aspen Security Forum to raise concerns about encrypted communications the FBI can't access, comparing ISIS militants to needles in a regional haystack.
"If you imagine a nationwide haystack, we are trying to find needles in that haystack. And a lot of those needles are invisible to us either because in they are communicated or just because they have communicated in a place that we can't see them," Comey said. "And knowing there are needles out there that you can't see is very worrisome."
Comey said Wednesday SIS has become a bigger threat to the United States than al Qaeda.
"The threat that ISIL presents and poses to the United States is very different in kind, in type and degree than al Qaeda," Comey said. "ISIL is not your parents al Qaeda. It's a very different model. And by virtue of that model, it's currently the threat we are worried about in the homeland most of all."
The Pentagon announced Tuesday Muhsin al Fadhli, a Kuwaiti-born jihadi and leader of the Khorasan Group, was killed earlier this month in a targeted strike. The strike happened July 8 while Fadhli was traveling to Sarmada. Syria.
"His death will degrade and disrupt ongoing external operations of al-Qaeda against the United States and our allies and partners," Pentagon spokesman Capt. Jeff Davis said in a written statement.
While terrorist groups like ISIS and the al Qaeda affiliate Jabhat al-Nusra are responsible for much of the violence inside Syria, the Khorasan Group was believed to direct most of its energy plotting external attacks in the West.
Comey also said Wednesday that investigators haven't determined why Mohammad Abdulazeez carried out the shootings that killed four Marines and a sailor last week in Chattanooga, Tennessee. He said the FBI is determined to "understand every second of his life" for the last two years, at least.
Comey said the prospect of a terrorist group launching a cyberattack on the United States is a small but growing problem.