FBI Tracking Nearly 800 ISIS-Related Cases Across US, FBI Director Says FBI Director James Comey said online propaganda remains a serious threat.

 -- Of the nearly 1,000 FBI cases across the country looking at people who may have been radicalized online, about 80 percent of them are tied to ISIS, FBI Director James Comey said today.

"[ISIS'] ability to motivate troubled souls, to inspire them, remains a persistent presence in the United States," Comey said. "We have north of 1,000 cases where we’re trying to evaluate where somebody is on the spectrum from consuming [ISIS propaganda] to acting, and that number continues to tick up slowly."

However, Comey said ISIS -- also known as the Islamic State -- has been losing its ability to recruit people to Iraq or Syria, with the FBI seeing a "drop in the number of people traveling or attempting to travel" overseas to join the group.

"The so-called Islamic State brand has lost significant power in the United States," Comey said. "They’ve lost their ability to attract people to their Caliphate from the United States."

In 2014 and the first half of 2015, the FBI was seeing as many as 10 people a month trying to leave the United States for ISIS, but over the past year that number has averaged about one per month, according to Comey.

"So, there’s no doubt that something has happened that is lasting in terms of the attractiveness of the nightmare which is the Islamic State to people in the United States," Comey added.

Comey also said the so-called "kill lists" that ISIS is posting online are becoming less sophisticated.

"What’s interesting is their lists have gotten less specific and more like they just pulled it out of the phone book or found it on a website somewhere," Comey said. "I don’t know exactly what that shows. But you remember two years ago they were focused on particular lists of service members, now they’re drifting towards just putting out hundreds and hundreds of people that they pulled off some [public database]."

Nevertheless, Comey said the FBI takes the lists "very seriously" and tries to notify anyone mentioned out of an abundance of caution.

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