ISIS is threatening more attacks like the one over the weekend in Texas at an event to draw the Prophet Muhammad cartoon contest. The latest post says ISIS has 71 trained soldiers in 15 states ready to attack.
Five of the states were named in the online message include Virginia, Maryland, Illinois and California - and Michigan.
Andy Arena, the former special agent in charge of the FBI in Detroit, said that the terrorist organization thrives on fear.
"I think this is part of ISIS' plan to put that out and really scare people," Arena said. "From that standpoint, they succeed, they win."
Arena was in charge of counter-terrorism after 9/11 and says it's not clear if ISIS has truly trained these alleged operators or if they are people who have been radicalized at a computer screen.
"There are people who went over and who have attempted to go over and fight and train," Arena said. "I think the federal government is tracking those people. They've actually arrested several attempting to leave the country. They are going to get charged for material support.
"The trickier part is the people sitting on the internet."
Arena says that social media platform is a tough place to monitor for terrorist activity.
"They can sit in mommy and daddy's basement on the laptop and never leave the house," Arena said. "They can become radicalized, inspired, trained and operationalized and never leave the house."
"And to me that is the scary piece."
But Arena does not advocate living in fear.
"If we change the way we live in this country, then they win," he said. "And we don't want them to win."
Arena says the safety rules for the average citizen remains, live your life. But as always, if you see something, say something.