Middle East 14 September 2014 Islamic State video shows beheading of British aid worker David Haines The Islamic State video appears to show the killing of a third Western hostage, aid worker David Haines, and ends with the warning that another British person will be next. David Haines was captured in Syria in March 2013. Sign UpGet the New Statesman's Morning Call email. Sign-up The jihadi group Islamic State has released a video that appears to show the beheading of the British aid worker David Haines. Haines was captured in Syria in March 2013. The video is similar to two others released by Islamic State in recent weeks depicting the deaths of two US journalists, James Foley and Steven Sotloff. The executioner, who is masked in all three videos, seems to speak with a British accent. At the end of the video, Islamic State warns that a second British hostage would be next to die. Haines, who is 44 and has two children, was working for the aid agency Acted when he was captured and had previously delivered humanitarian aid to people in Libya and South Sudan. In the last week the US has launched at least nine airstrikes on Islamic State, which controls territory in both northern Iraq and Syria. The UK has delivered heavy weapons and ammunition to Iraqi authorities trying to halt the advance of the militants. In a statement, Prime Minister David Cameron described the killing of Haines as “an act of pure evil”, adding that “we will do everything in our power to hunt down these murderers and ensure they face justice, however long it takes.” Cameron is due to hold a Cobra emergency meeting later today to discuss the situation. › 50 years of David Dimbleby Sophie McBain is a special correspondent at the New Statesman. She was previously an assistant editor. Subscribe For more great writing from our award-winning journalists subscribe for just £1 per month!