© AFPAbu Bakr al-Baghdadi
The video -- released by the IS's media outlet, Al-Furqan, on April 29 -- shows Abu Bakr al-Baghdadi appearing with an unkempt, bushy gray and red beard while sitting on the floor against a wall. He is wearing a black robe with a light vest over it and has a machine gun near his right arm. Three masked men are seen listening to him speak.
Baghdadi -- speaking slowly and often pausing -- says the IS group will gain revenge for the killing and imprisonment of its fighters. He says his group's operations against the West are a "long battle."
It is unknown where the 18-minute video was taken and both Iraqi and U.S.-backed forces are seeking to capture the extremist leader.
A State Department spokesman said it will review the recording and allow the "intelligence community to confirm its authenticity."
He added that the U.S.-led coalition will "ensure an enduring defeat of these terrorists and that any leaders who remain are delivered the justice that they deserve."
Baghdadi, 47, last appeared in a video while delivering a sermon at the Al-Nuri Mosque in 2014 in the Iraqi city of Mosul, which had been taken by IS forces when they swept over large swathes of Iraq and Syria. It was during that speech that he declared the establishment of an Islamic caliphate.
The SITE Intelligence group said Baghdadi spoke in the video about the conclusion of the battle in Baghuz, which was the last IS stronghold in Syria before falling to the U.S.-backed forces.
A date on the video said it had been recorded in April. But the authenticity and date of the video cannot be verified.
Baghdadi also discussed the recent bombings in Sri Lanka that killed more than 250 people and claimed those attacks were carried out in retaliation for the fall of Baghuz. "This is part of the revenge waiting for the crusaders," he added.
Baghdadi has been reported killed or injured several times in recent years.
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