Islamic State militants have released footage claiming to show the beheading of British hostage David Haines.           

The aid worker, 44, was captured by ISIS in Syria in March 2013.           

The plight of the dad-of-two was revealed when he appeared at the end of a video showing the beheading of US journalist Steven Sotloff earlier this month.           

ISIS had threatened to kill Mr Haines if world leaders do not bow to their demands.

Tonight, the extremists posted a new video lasting 2minutes and 30 seconds which appears to show the beheading of David Haines.

At the end of the video, ISIS parade another hostage.           

The militants have not responded to any of the family's attempts to make contact so far, the Foreign and Commonwealth Office (FCO) said.