CHICAGO (CBS/AP) — Republican U.S. Sen. Mark Kirk says the United States should take a hard line against the Islamic State group.

Islamic State extremists released a video Tuesday purportedly showing the beheading of a second American journalist. It also warns President Barack Obama that as long as U.S. airstrikes against the group continue there’ll be continued violence.

Kirk calls the reported beheading cruel and barbaric. He says the U.S. should take effective military action. He also told reporters Tuesday after an unrelated event in Chicago that Obama should “bomb the hell out of them.”

Kirk says there’s little hope that those who are in the hands of the group will return.

“Given ISIS’ ideology, and given the fact that they probably own a couple a million people, and given the nature of freelance journalism, from the journalists of what I have seen the journalists have entered the battle space via Turkey. The Turks could really help us cut down that flow.”

If freelance journalists don’t stay out of the area, Kirk says perhaps they can be kept out.

CBS 2 security expert Ross Rice says a key worry is if one of the U.S. citizens fighting and dying for ISIS returns.

“They’re the ones that are gonna hurt us. They are U.S. citizenship, they have passports and can get in the country and they can carry out a terrorist attack at the behest of ISIS,” Rice said. “We saw what two people can do in Boston it doesn’t take much.”

The Islamic State has conquered wide territory across Syria and Iraq and has declared itself a caliphate.

(TM and © Copyright 2014 CBS Radio Inc. and its relevant subsidiaries. CBS Radio and EYE Logo TM and Copyright 2014 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed. The Associated Press contributed to this report.)

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