ISIS Video Purportedly Shows Mass Execution of 21 Egyptian Christians

Egyptian President Sisi vows to punish ISIS for the beheadings

Fox News reports that the Egyptian men were captured in Libya by ISIS, most of them traveling there in search of work.

Islamic State released a video on Sunday purporting to show the militant group beheading 21 Egyptian Christians kidnapped in Libya.

In the video, militants in black marched the captives, dressed in orange jump suits, to a beach. They were forced down onto their knees, then beheaded. The video appeared on the Twitter feed of a website that supports Islamic State.

A caption on the five-minute video read: "The people of the cross, followers of the hostile Egyptian church."

Thousands of Egyptians have traveled to neighboring Libya in search of jobs since an uprising at home in 2011, despite advice from their government not to go to one of the most dangerous countries in the region.

Before the killings, one of the militants stood with a knife in his hand and said: "Safety for you crusaders is something you can only wish for."