The leader of so-called Islamic State (IS) has appeared in a video for the first time in five years.
Speaking in the footage, Abu Bakr al-Baghdadi acknowledges the group's defeat in their last stronghold in Syria, but vows a "long battle" and "revenge" ahead.
The video was posted on al-Furqan media network and IS, also known as Daesh, stated the recording was shot in April.
US officials said they are still working to confirm the authenticity of the video message.
It is al-Baghdadi's first video appearance since he delivered a sermon at the al-Nuri mosque in the Iraqi city of Mosul in 2014.
Dr. Lewis Herrington, a terrorism expert from Loughborough University, believes the video is "absolutely" genuine.
"I think this is the start of a new era for the Islamic State, unable to retain ground.
"It is now a case of actually inflicting significant revenge against the west.
"I think that what we'll see now is that Sri Lanka is just the beginning."
The United States has reiterated its determination to defeat the Islamic State group after IS released a video purporting to show its leader Abu Bakr al-Baghdadi for the first time in five years.
The State Department said it was clear the fight against IS was not finished, despite its loss of territory in Syria and Iraq.
The UK's contribution to the fight against IS, Operation Shader, will continue, despite the loss of ground.
The final towns and cities once held by the militant group were liberated last month, with confirmation coming from the US-backed Syrian Democratic Forces (SDF).
The battle to capture Baghouz lasted for weeks amid an unexpected exodus of civilians from the area.