An airstrike targeting the British IS militant Mohammed Emwazi, known as Jihadi John, has been carried out in Syria by US forces.
The extremist appeared in a number of beheading videos, including those in which Salford aid worker Alan Henning was killed.
Pentagon press secretary Peter Cook said it was not clear whether Emwazi had been killed in the strike in Raqqa.
Emwazi was first seen, with his face covered, in a video in August 2014 which showed the beheading of US journalist James Foley.
He also appeared in videos showing the killings of American journalist Steven Sotloff, and worker Abdul-Rahman Kassig and Japanese journalist Kenji Goto.
It was not until February this year that the jihadist was unmasked as Kuwaiti-born Emwazi, who lived in the UK since the age of six.
"The killing of Mohammed Emwaz in Syria is a significant moment in the fight to get justice for Alan Henning, David Haines and all the victims of this evil man.