ISIS Targeting Military Personnel through Social Media

The FBI is warning members of the U.S. military to protect themselves from a potential attack by ISIS on U.S. soil. The agency is urging military personnel to erase all information on social media accounts that could help "violent extremists" learn their identitites.

In an unprecedented joint intelligence bulletin, the FBI and Department of Homeland Security say they have intelligence that ISIS is trying to recruit people in the United States to target members of the military, using social media to track them down.

It's the strongest warning to date about possible attacks by ISIS.

"It's sort of like be on the lookout for or change your behavior because we believe it could potentially put you in harms way," Brad Garrett, a former FBI agent, told ABC News.

"We understand that you are young, you communicate through social media, but we are telling you that's how ISIS finds people they potentially target," Garrett said.

A portion of the bulletin says, "The FBI recently received reporting indicating individuals overseas are spotting and assessing like-minded individuals who are willing and capable of conducting attacks against current and former U.S.-based members of the United States military."

As America continues to target ISIS positions in Syria and Iraq, Homeland Security officials are increasingly concerned about reprisal attacks within our borders.

Last month's terror attacks in Canada have officials especially worried. Two young men claiming to be inspired by ISIS killed two uniformed Canadian soldiers in Ottawa.

The FBI and DHS say those incidents may "embolden" and "motivate" ISIS sympathizers to carry out similar attacks.

Dr. Jonathan Schanzer, with the Foundation for the Defense of Democracy, told CBN News that ISIS is targeting members of the military because they're engaged in the fight against terrorism.

Dr. Jonathan Schanzer spoke with CBN News about the FBI's warning to military personnel. Watch the full interview here:

Here at home they won't be carrying a gun or wearing the protection that they might be in a war zone.

"The really scary thing is that there appears to be some network that exists here in the United States that belongs to ISIS," Schanzer told CBN News.

According to ABC News, some U.S. Special Forces personnel began deactivating their social media accounts several months ago.

When it comes to scrubbing social media accounts, experts say to delete anything that tells your location, information about what you're doing for the military and when, and any posts that share your opinion about ISIS or the fight against them.

These new warnings come as an ISIS affiliate in Egypt claimed responsibility for killing American oil worker William Henderson. The FBI said it's skeptical of the claims, but it's investigating.

On September 21, a day before the start of U.S. operations against ISIS in Iraq and Syria, the terror group's leader issued an audio message calling on Muslims to attack members of the military in the United States and Europe.

"Do not ask for anyone's advice and do not seek anyone's verdict. Kill the disbeliever whether he is civilian or military, for they have the same ruling. Both of them are disbelievers. Both of them are considered to be waging war," Abu Mohammad al-Adnani said in an audio speech posted online.