The Islamic State (Isis) group has released a video purportedly showing a Jordanian pilot it has held hostage being burnt alive.

The horrific footage, the authenticity of which could not be immediately verified, allegedly shows Muath al-Kaseasbeh wearing an orange jumpsuit inside a cage.

A line of fuel leading to him is then lit up and the pilot is engulfed by flames.

The footage comes after negotiations to secure his release crumbled after IS beheaded Japanese journalist Kenji Goto, whose life was initially linked to that of al-Kaseasbeh.

Pictures allegedly showing a Jordanian pilot being taken hostage by militants after his plane was shot down near Raqqa, Syria.
Jordanian pilot Muath al-Kaseasbeh as he was captured by militants

The pilot, 26, was captured by the Islamist militants in December, as his F-16 crashed near the IS stronghold of Raqqa, Syria.

Last week, IS released an audio message demanding that Jordan frees Sajida al-Rishawi, an Iraqi woman facing the death penalty for the 2005 bombings that killed 60 people at hotels in the Hashemite kingdom, in exchange for Goto.

The message also threatened to kill al-Kaseasbeh if al-Rishawi was not released.

Hostage stand-off

"If Sajida al-Rishawi is not ready for exchange for my life at the Turkish border by Thursday sunset, 29 January, Mosul time, the Jordanian pilot Moaz al-Kasasbeh will be killed immediately," the captive Japanese journalist was heard saying in the audio message.

Jordan agreed to release the woman if its pilot was also included in the prisoner swap but demanded proof he was still alive.

A deal was however never reached and IS released a video showing the beheading of Goto over the weekend. Three days later the terror group has published the gruesome video apparently showing the murder of al-Kaseasbeh.

During the negotiations Jordan threatened to execute all of its death row inmates with ties to IS, according to The Times.

Jordan is a member of the US-led coalition carrying out air strikes against the extremist group in Iraq and Syria.