Using social media to track extremists online

U.S. authorities are tracking a man whom they say is influencing Islamic State of Iraq and Syria(ISIS) followers from his home in Michigan -- using social media to inspire jihad.

Ahmad Musa Jibril is a Palestinian-American cleric whose extremist views caught the attention ofU.S. law enforcement.

His alleged call for jihad in 2005 led federal prosecutors to describe him as a man who "encouragedhis students to spread Islam by the sword, to wage a holy war" and "to hate and kill non-Muslims."

Ahmad Musa Jibril

CBS News

In 2012, Jibril was released from federal prison after serving six years for insurance fraud. He iscurrently living in Dearborn, Michigan, where he's on probation.

Even under law enforcement supervision, he's become one of the most influential figures for westernforeign fighters, according to British researcher Peter Neumann.

"We counted all their likes, their mentions and their follows and what turned out to be true is thatAhmad Jibril was liked by an astonishing percentage of foreign fighters," Neumann says.

According to Neumann's research, 60 percent were following him on Facebook, favoriting his tweetsand retweeting his messages.

Last year, a federal judge heavily restricted Jibril's ability to use social media. As a result, hisaccounts have gone dormant. And yet his Facebook page has grown from 211,000 likes last year to245,000 today.

Jibril declined CBS News' requests for an interview. His probation ends in one month. Without newcharges, he is free to go back online without restrictions.

He's toned down his rhetoric, suggesting maybe he's a changed man. Some aren't convinced.

"There is nothing to suggest he has changed his views," Neumann says. "He has toned them downbecause he realizes that if he doesn't tone them down they will come after him."

That is the dilemma law enforcement deals with everyday: How best to identify potential threats whomay mask their true intent.

But social media can also help law enforcement with important clues about who and whereextremists might be. That could escalate to monitoring emails, texts and phone conversations, all ofthat under court orders.

The FBI looks graphic design resume at hundreds of people who may have terrorist leanings andopens investigations into some of those cases. FBI Director James Comey confirmed Wednesday thebureau has now opened investigations in all 50 states.

Law enforcement has been very public about the damage they believe Edward Snowden caused tointelligence gathering in the U.S. by disclosing information about the NSA's surveillance program.

Director of National Intelligence James Clapper has said that Snowden caused a significant blow tonational security by exposing and compromising intelligence gathering tactics.

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