An ISIS affiliate released a video Wednesday threatening to kill a Croatian hostage if Egyptian authorities do not release "Muslim women" held in prison within 48 hours, a day before the country plans to unveil a highly promoted new extension of the Suez Canal. The video, circulated on social media by ISIS sympathizers, shows a man wearing a yellow jumpsuit kneeling in the desert before a knife-wielding masked man in military fatigues. A black Islamic flag often used by the extremists flutters next to him. The video identifies itself as coming from the media arm of the ISIS affiliate in Egypt's lawless Sinai Peninsula. Reading calmly from a note in English, the man identifies himself as Tomislav Salopek, a married, 30-year-old father of two, adding that ISIS fighters captured him on July 22. If Egyptian authorities do not act, he said, "the soldiers from Wilayet Sina will kill me." Wilayet Sina is the Arabic phrase for the Egyptian group calling itself the Sinai Province of the Islamic State.

It was not clear where the video was shot. The Associated Press could not independently verify the footage, entitled "A Message to the Egyptian Government," though it was shot in the style of previous ISIS propaganda videos in which they threaten and behead hostages.