Footage has emerged appearing to show Islamic State leader Abu Bakr al Baghdadi alive and talking about this month's Sri Lanka bombings.
The leader, whose death or serious injury has been reported repeatedly in the past, appears well despite recent claims about his health.
A bearded man who resembles Baghdadi sits cross-legged on the floor next to a machine gun and gives an 18-minute speech in the footage, which is in the process of being verified by Sky News.
If the man is Baghdadi, this is his first appearance in a IS video in five years. He appears older and heavier than in previous images.
His importance in IS today is unclear, with intelligence suggesting he had become a figurehead rather than a strongman in the terror group.
Despite this, he is the world's most wanted man, with a ransom of $25m (£19m) on offer.
The man speaks slowly and unsteadily. He says he will seek revenge for those who had been killed or imprisoned in the fight against his group.
He acknowledges that IS lost the battle in Baghouz, the last geographical stronghold of the terror group which fell in March.
The footage, which was dated April this year, was posted online by Islamic State's Al Furqan media network.
In the clip, he praises the Easter Sunday Sri Lanka attackers, who claimed to be acting as part of IS.
The bearded man is accompanied by at least three other men, two with their faces covered and another wearing a keffiyeh (a type of headscarf).
Baghdadi, who has led the group in its form as IS since 2013, made his first video appearance in Mosul in 2014 where he declared the caliphate at Iraq's Great Mosque of al-Nuri.