An online video purportedly from Islamic State"s Egypt affiliate showed a Croatian hostage working for a French company who said the group would kill him in 48 hours if Muslim women in Egyptian jails were not freed.

In the video, titled "A message to the Egyptian government" and posted on online forums, a man is seen kneeling and wearing a short-sleeved orange jumpsuit, like those worn by previous Western prisoners in Islamic State videos who were later killed.

He identified himself as Tomislav Salopek, 30, from Croatia. Zagreb said it was doing all it could to resolve the situation.

The Egyptian government has not  commented on the fact.yet done so. The Croatian citizen was kidnapped on July 22, when he was traveling in the direction of Cairo.