A video released online by an Islamic State propaganda source claims to show a captive Jordanian pilot being burned to death.
The video, published by IS militants, claims to show pilot Moaz al-Kasasbeh, being burned alive.
The pilot was captured in December and Jordan has since been attempting to secure his release in a prisoner swap deal.
A relative of Moaz al-Kasasbeh has told Reuters news agency that the Jordanian military confirmed to family members that the pilot had been killed.
“The military forces announce that the hero pilot, Moaz al-Kaseasbeh, has fallen as a martyr, and ask God to accept him with the martyrs,” Mamdouh al-Ameri, a spokesperson for the Jordanian Military, said in a statement read on Jordanian TV.
“While the military forces mourn the martyr, they emphasize his blood will not be shed in vain. Our punishment and revenge will be as huge as the loss of the Jordanians.”
Michael Haines, brother of the murdered British IS hostage David Haines, said: “My heart is filled with sadness yet again to hear of the savage murder of another hostage by the terrorists (IS).
“Firstly, my thoughts and prayers go out to the family of Moaz al Kasasbeh, I know only too well the feelings of loss, anger and disbelief they must be experiencing right now. I share their pain.
“The murder of Moaz al Kasasbeh once more shows the unmerciful nature of these criminals.
“The world must come and stand together in the rejection of the fear the terrorists are attempting to spread. Only when we are all united against this vile threat will we defeat it.”
Moaz al-Kasasbeh’s death comes three days after a video of Japanese hostage Kenji Goto was released, showing a member of IS beheading him.
Both videos were distributed via a Twitter account known to act as a source for IS propaganda.