BREAKING NEWS ISIS release video claiming to show beheading of British hostage David Haines

Father-of-two from Perth, Scotland, abducted by militants in Syria last year 
He was shown on knees in jihadi video of US journalist being beheaded  
In the footage, the extremists also threaten to execute another Briton
Militants previously beheaded journalists Steven Sotloff and James Foley

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.

Mr Haines was born in East Yorkshire United Kingdom but raised in Perthshire, and before his capture was living in Croatia with his second wife Dragana.

He has a 17-year-old daughter with his first wife Louise, and a four-year-old daughter with Dragana who described him as a "fantastic man and father".

Mr Haines was taken while working for ACTED, having previously helped people in Libya and South Sudan.

Militants from IS have beheaded two American journalists, Jim Foley and Sotloff, posting the evidence online in gruesome videos featuring a masked jihadist with a British accent.

Foreign Secretary Philip Hammond has said the FCO will be doing "everything" they could to protect Mr Haines.

Educated at Perth Academy secondary school, he has worked for aid agencies in some of the world's worst trouble spots, including Libya and South Sudan.

He was in Libya during its civil war in 2011, working as head of mission for Handicap International, which helps disabled people in poverty and conflict zones around the world.