The terrorists known as ISIS released a video on Sunday that seems to show the militant group beheading 21 Egyptian Christians kidnapped in Libya.
The Egyptians, dressed in orange jump suits, were beheaded after being forced down on the ground on a beach. An early caption in the video says the location is "Wilayat Tarabulus by the Mediterranean Sea," which suggests that it was filmed near Tripoli.
Each of the victims, who are all male, is paired with a masked, knife-wielding terrorist and, after a brief statement by the ISIS leader, they are all beheaded.
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The video is called "A Message signed with blood to the nation of the cross" and was released by the group's Al-Hayat Media Center, according to Flashpoint Intelligence, a global security firm and NBC News consultant.
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"This undeniably means that the group now views Christian populations as not only targets but also part of the bigger 'Crusader plot,' not separate from the US-led coalition or aggressors," a Flashpoint report said. "The group's message is highly intimidating and it somewhat challenges the Western nations to intervene and save the Christians as it intervened to save the Yazidis and others."
The video appeared on the Twitter feed of a website that supports ISIS.
Egypt's official state news agency said that Egypt's Coptic Church spokesman confirmed the killings. Egyptian President Abdel Fattah el Sisi has convened the National Defense Council to discuss the murders and he has also declared seven days of national mourning.