Islamic State claims US hostage Kassig beheaded

An undated photograph made available by the Special Emergency Response and Assistance shows US aid worker Peter Kassig at an unknown location in Syria. Islamic State has released a video purporting to show the killing of Kassig, who was captured by militants in Syria in October 2013.

Reuters/AFP/Cairo/Beirut

Islamic State militants fighting in Iraq and Syria claimed in a video posted online on Sunday that they had beheaded American hostage Peter Kassig.

The video did not show the beheading but showed a masked man standing with a decapitated head covered in blood lying at his feet. Speaking in English in a British accent, the man says: "This is Peter Edward Kassig, a US citizen."

Reuters could not immediately verify the authenticity of the footage, which appeared on a jihadist website and on Twitter feeds used by Islamic State.

Kassig, a 26-year-old from Indiana, is also known as Abdul-Rahman, a name he took following his conversion to Islam while in captivity.

Kassig's parents have said through a spokesperson their son was taken captive on his way to the eastern Syrian city of Deir al-Zor on October 1, 2013.

A former soldier, Kassig was doing humanitarian work through Special Emergency Response and Assistance, an organisation he founded in 2012 to help refugees from Syria, the family has said.

If confirmed, Kassig's beheading would be the fifth such killing of a Westerner by Islamic State, following the deaths of two US journalists and two British aid workers.

In an apparent reference to testimony about Kassig by former fellow captives, the masked man says: "Peter, who fought against the Muslims in Iraq while serving as a soldier under the American army, doesn't have much to say. His previous cellmates have already spoken on his behalf."

The announcement of Kassig's death formed part of a 15-minute video in which the group issued warnings to the US, Britain and others including Shia Muslims.

It also shows militants beheading several men identified as pilots and officers loyal to Syrian President Bashar al-Assad.

British Prime Minister David Cameron said he was horrified by the "cold-blooded murder".

Britain's Foreign Office said it was analysing the video.

US says working to confirmThe United States said Sunday it was working as quickly as possible to confirm the authenticity of the video."If confirmed, we are appalled by the brutal murder of an innocent American aid worker and we express our deepest condolences to his family and friends," National Security Council spokeswoman Bernadette Mehan said.  The same video showed the simultaneous beheadings of at least 18 men described as Syrian military personnel, the latest in a series of mass executions and other atrocities by IS militants.