The FBI are closing in on American ISIS executioner after a wave of 'substantial leads' following a public appeal for help in identifying him. The unknown man, who has appeared in a propaganda video released by the terror group, is believed to be from the United States because of his pronounced American accent. Today a senior FBI official told ABC News that new leads possibly included a man with a 'North American' accent who appeared in the clip. Scroll down for video The FBI are closing in on American ISIS executioner after a wave of 'substantial leads' following a public appeal for help in identifying him
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FBI released a portion of a mid-September ISIS propaganda video
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The video features a man believed to be North American
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Bureau reached out to the public asking for help identifying the man
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In the video, the jihadist spoke while Syrians dug their own graves
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FBI Director: Dozen Americans are believed to be fighting alongside ISIS
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'We continue to call on the public to report suspicious activity of travelers in support of a terrorist organization or information about the subject speaking with a @placeholder accent in the video issued by ISIL on September 19.
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The U.S. government has estimated that more than 100 @placeholder have left the country to fight with ISIS, some of whom have now come back.
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The @placeholder reports that U.S. citizens traveling overseas to fight alongside terrorist groups is nothing new.