01:17 - Source: CNN
NYPD to help FBI track ISIS supporters
(CNN) —  

FBI Director James Comey said Thursday his agency does not yet have the capabilities to limit ISIS attempts to recruit Americans through social media.

It is becoming increasingly apparent that Americans are gravitating toward the militant organization by engaging with ISIS online, Comey said, but he told reporters that “we don’t have the capability we need” to keep the “troubled minds” at home.

“Our job is to find needles in a nationwide haystack, needles that are increasingly invisible to us because of end-to-end encryption,” Comey said. “This is the ‘going dark’ problem in high definition.”

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Comey said ISIS is increasingly communicating with Americans via mobile apps that are difficult for the FBI to decrypt. He also explained that he had to balance the desire to intercept the communication with broader privacy concerns.

“It is a really, really hard problem, but the collision that’s going on between important privacy concerns and public safety is significant enough that we have to figure out a way to solve it,” Comey said.

The FBI director has previously said these apps are constantly reminding potential supporters to carry out attacks. One of the gunmen who carried out an attack at a “Draw Mohammed” cartoon contest in Texas last month is believed to have used Twitter to communicate with ISIS.

“It’s almost as if there is a devil sitting on the shoulder saying ‘Kill, Kill, Kill, Kill!’ all day long,” Comey said then.