Footage appears to show the leader of the Islamic State group for the first time in five years alive and vowing to seek revenge for its loss of territory.
The man said to be Abu Bakr al-Baghdadi in the video claimed the Easter Sunday bombings in Sri Lanka were "part of the revenge" that awaits the west after the group lost its last stronghold in Syria.
The video, released by the extremist group's propaganda arm Al-Furqan on Monday, shows al-Baghdadi with a bushy grey and red beard, wearing a black robe with a beige vest and seated on the floor with what appears to be a machine gun propped up next to him.
He is speaking with three men seated opposite him whose faces were covered and blotted out.
It is his first video appearance since he delivered a sermon at the al-Nuri mosque in the Iraqi city of Mosul in 2014. The leader appears well despite recent reports that he was thin and frail.
Al-Baghdadi acknowledged in the video that IS lost the war in the eastern Syrian village of Baghouz, the group's last sliver of territory, which was captured last month by the US-backed Kurdish-led Syrian Democratic Forces.
The fall of Baghouz marked the militants' territorial defeat and the end of their self-declared Islamic caliphate over parts of Syria and Iraq.
Al-Baghdadi said that the battle for Baghouz demonstrated the "barbarism and brutality" of the West and the "courage, steadfastness and resilience of the nation of Islam."
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"This steadfastness shocked the hearts of the Crusaders in what increased their rage," he added.
Referring to the setbacks in battle, he said the "brothers" of the many fallen fighters "will avenge that, as they will not forget as long as they have blood in their veins, and there will be a battle after this one."
It is unclear when or where the video was filmed. Al-Baghdadi appeared to be in good health, although he spoke slowly and haltingly in the video.
Despite numerous claims about his death in the past few years, al-Baghdadi's whereabouts remain a mystery. He appeared in public only once, in 2014. Since then, many of his top aides have been killed, mostly in US-led coalition airstrikes.
