Croatian threatened with execution by IS affiliate in Egypt

The Islamic State affiliate in Egypt, the Sinai Province group, threatened on Wednesday to execute a Croatian kidnapped in Cairo last month within 48 hours.

He is the first foreigner to be abducted and threatened with death by militants in Egypt since an insurgency began two years ago.

In a video posted online, the Croatian identifies himself as Tomislav Salopek working for French company CGG, and appears to be wearing an orange jumpsuit similar to previous Western prisoners and kneeling at the feet of a hooded man holding a knife. The Islamic State flag is unfurled in the background.

Reading from a sheet of paper, he says he will be executed within 48 hours if Egypt's government fails to release Muslim women held in prisons.

Salopek did not say when the countdown began. 

In Zagreb, the foreign ministry said the "Croatian government... is doing its best to solve as soon as possible the difficult situation in which the Croatian citizen T.S. is," identifying the hostage only with his initials.

"Considering the very difficult and sensitive circumstances and in order not to make a difficult situation worse, we are not able to provide more detailed information at this moment."

The French firm, CGG, which provides software for oil exploration and production, confirmed that the man in the video was one of its "sub-contracted staff working on a land acquisition seismic crew" and that he had been "kidnapped on 22 July while in transit in Cairo".

"He is the hostage appearing on the video released today by the Sinai Province of Islamic State," it said, without naming him.

No news agency or state government has verified the video's authenticity thus far.