A video apparently showing the beheading of British hostage Alan Henning has been released on the internet.
The footage appears to show the 47-year-old aid worker, who was kidnapped last December in Syria by IS militants, kneeling beside a militant dressed in black in a desert setting.
Mr Henning, a former taxi driver from Salford, was last seen at the end of a video released last month following the beheading of fellow British captive David Haines.
The video appears to show Mr Henning say: ``I am Alan Henning. Because of our Parliament's decision to attack the Islamic State, I, as a member of the British public, will now pay the price for that decision.''
The man dressed in black, who speaks with a British accent, then makes a direct statement to Prime Minister David Cameron: “The blood of David Haines was on your hands Cameron. Alan Henning will also be slaughtered, but his blood is on the hands of the British Parliament.”
The video then apparently shows the militant alongside former American soldier Peter Kassig.
The militant says: “Obama, you have started your aerial bombardment in Sham [Syria], which keeps on striking our people. So it is only right that we continue to strike the necks of your people.”
The British Foreign Office said: “We are aware of the video and are working urgently to verify the contents. If true, this is a further disgusting murder.
“We are offering the family every support possible; they ask to be left alone at this time.”
Earlier this week Mr Henning's wife Barbara pleaded for him to be freed.
She said: “I ask Islamic State please release him, we need him back home.”
She added: “Some say wrong time, wrong place. Alan was volunteering with his Muslim friends to help the people of Syria. He was in the right place doing the right thing.”
Mrs Henning revealed she had received an audio message of her husband pleading for his life, and had been told that a Sharia court had found him innocent of being a spy.
She told BBC News: “We are at a loss why those leading Islamic State cannot open their hearts and minds to the truth about Alan’s humanitarian motives for going to Syria and why they continue to ignore the verdicts of their own justice system.
”Surely those who wish to be seen as a state will act in a statesmanlike way by showing mercy and providing clemency. I ask again, supported by the voices across the world, for Islamic State to spare Alan’s life.“