Could Executioner in Mass Beheadings Be American?

The masked jihadi in a gruesome video depicting the mass beheadings of 21 Egyptian Christians could reportedly be an an American convert to the Islamic State (ISIS).

The video released Sunday is being analyzed for clues when the militant talks about the execution as retaliation for Osama bin Laden's slaying by Navy SEALs in 2011, the New York Post reports.

"They are analyzing the video now, using facial recognition and they continue to analyze his speech patterns," an unnamed U.S. official tells the Post. "He sounds American to me."

North Carolina State University linguistics expert Erik Thomas tells ABC News that based on distinctive word pronunciations, he also believes the jihadi "sounds like an American" with some Arabic influence mixed in.

The same kind of analysis helped identify "Jihadi John" in videos of several beheadings believed to have shot in Syria, ABC News reports. Though authorities say they know the militant is a British citizen, they've not publicly named him.

"We know they are trying to actively recruit Americans," the U.S. official tells the Post. "By using somebody with a clear American voice, they assess that they will get into the minds of Americans, make them nervous and scared."

There are 3,000 Westerners fighting in Syria and Iraq, the U.S. official tells the Post; some 150 are Americans.

"They would love nothing more than to have one of these American converts fly back to the United States with an American passport to create terror and make you lose sleep at night," the U.S. official tells the Post.

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