Site, an intelligence group which was the first to report Steven Sotloffs beheading, confirmed the videos release.
Haines, who was 44, was kidnapped last year. He had been in Syria for just three days when he was kidnapped and handed over to Islamic State (Isis) militants.
The murder comes one day after the Haines family released a statement urging his captors to contact them.
The aid worker was taken while working for Acted in Syria in March 2013, having previously helped people in Libya and South Sudan.
http://www.theguardian.com/world/2014/sep/13/isis-video-david-haines-beheading
“The aid worker”
People with good in their heart, being killed by people filled with hate.
Did they show another hostage at the end of the video?