There has been no direct threat made yet, but top Homeland Security officials are concerned the Islamic State in Iraq and Syria may try to launch an attack on U.S. soil in the not-too-distant future.

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"What's troublesome to us here in the States and parts of Europe is we have many fighters that went to join ISIS in Syria, in Iraq, who hold American and British passports -- a significant number," said terrorism expert Harvey Kushner, professor of political science at Long Island University. "This a nightmare scenario for us here in the States because there's concern with someone who has an American passport and can travel very freely."

Kushner said at some point, the U.S. probably will be targeted by what he calls a formidable opponent.

"It's the first time we've seen a coalition of many jihadists to form their own state," he said. "Do they pose a threat? Absolutely."

According to Kushner, there are always terror concerns connected to New Jersey for several reasons, one of which is that the state is situated right to New York.

The terror threat hits close to home in other ways, Kushner said, because "there's significant populations who hold sympathy to the jihadis inside of New Jersey. There's a base of support within New Jersey, and also its proximity to symbolic targets, so that's why New Jersey is always in the crosshairs."

Authorities are more concerned than they have been in the last 15, 20 years. This is the nightmare scenario of the creation of a militant Islamic state with a face, with a name that poses a threat to the security of this country."

Kushner added local authorities are on alert and have been counseled by federal agencies, but average citizens need to stay alert as well.

"See something, say something," he said. "Don't take for granted that something looks strange; report it to the local authorities."