The agony of the families of a captured journalist and fighter pilot is continuing after a sunset deadline for a possible prisoner swap allegedly set by their Islamic State (IS) kidnappers passed with no clue whether they are still alive.

Jordan demanded proof last night that a pilot threatened with execution by the Islamic State group was alive, as a deadline set by the jihadists to free a female militant expired.

Experts are examining a recorded message said to have been from hostage Kenji Goto, extending the deadline for Jordan's prisoner-swap release of an Iraqi would-be suicide bomber linked to al Qaida.

“What has my child done wrong?...There’s no more time.”