ISIS Speaker in Egyptian Christians' Beheading Video May be American or Canadian: Voice Experts

The ISIS fighter who appeared in the gruesome video that showed the beheading of 21 Egyptian Christians could possibly be an American or Canadian, experts dealing with voice recognition technology in the probe related to the video have revealed.

The footage, released last week, showed the beheading of 21 people in what apears to be the first mass brutal slaughtering carried out by the group outside its stronghold territory of Syria and Iraq.

The lead jihadist in the video, who is seen wearing a brown mask, points his dagger towards the camera and speaking in an American accent. He said:

"Oh people, recently you have seen us on the hills of as-Sham and Dabiq's plain, chopping off the heads that have been carrying the cross for a long time.

"And today, we are on the south of Rome, on the land of Islam, Libya, sending another message."

The intelligence community is examining the footage and gathering forensic clues on the speaker, including his height, build, and choice of words.

The most important clue that could help authorities identify the jihadist, however, is his voice. According to experts, his English appears to be near-fluent.

The speaker in the video "definitely learned his English in the United State," Erik Thomas, a socio-phonetics researcher at North Carolina State University, told CNN. He added, however, that he demonstrated some foreign language or mother-tongue influence, which is most likely Arabic.

Thomas further told the American news channel that the jihadist's English sounded more like American than Canadian. He, however, doesn't have the accents of the east coast, urban south or the southern Midwest.

"It's remotely possible but highly unlikely that he learnt his English in a foreign location," he said stressing on the possibility that he is either an American or a Canadian. "His accent is just too good. Very few people can learn a second language that well if they weren't immersed in it."

Other experts also note that English is probably the man's second language although it is likely that he spent a good number of years in the United States or Canada.

"The speaker may have spent a long time in North America, because the speech is really too fluent just to have been learned abroad," said professor Bill Kretzschmar, author of the book "The linguistics of Speech."