Washington (CNN) -- Is a jihadist featured on a 55-minute video released by ISIS, warning the United States against getting in its way in Iraq and Syria, an American? That's the question being asked by U.S. intelligence officials as they analyze a recruitment video that features the jihadist, who speaks perfect English with a North American accent, orchestrating a mass execution. The United States is doing a voice analysis and comparing what it finds to people the intelligence community has been watching, the officials told CNN on Saturday. The analysis is in its initial stages, according to the officials. Officials see the killer's appearance in the video as significant because he comes across, they say, as articulate and persuasive -- a person of influence within the terror group.
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U.S. intelligence officials are analyzing the voice on a ISIS video
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They are comparing it with the voices of people being watched, officials told CNN
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The 55-minute video released by ISIS shows the jihadist leading a mass execution
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In the video, jihadist speaks first in Arabic, then in English
But the ISIS fighter -- who is masked and wearing a camouflage uniform -- seamlessly switches to @placeholder.