BREAKING: ISIS releases video of alleged beheading of British captive

RYM MOMTAZ and LEE FERRAN ---- ABC News 

A video has surfaced online that appears to show the beheading of British captive Alan Henningby a purported member of the terror group ISIS, who then threatens the life of an American hostage.

“I am Alan Henning. Because of our Parliament’s decision to attack the Islamic State [ISIS], I, as a member of the British public, will now pay the price for that decision,” Henning says in the video, before his apparent executioner speaks.

“The blood of [fellow slain captive] David Haines was on your hands, [British Prime Minister David] Cameron,” the black clad militant says. “Alan Henning will also be slaughtered but his blood is on the hands of the British Parliament.”

Henning then appears to be killed. Near the end of the video another hostage is seen alive, identified as an American, as the militant says it's right that his group targets Americans as the U.S. continues its aerial bombardment of ISIS targets.

Henning’s death follows that of Haines, a British aid worker, as well as two American journalists, James Foley and Steven Sotloff, who were all killed separately in a similar, brutal fashion.

The British Parliament voted late last week to join coalition airstrikes on ISIS targets in Iraq after Cameron made a passionate plea to lawmakers.

“This is about psychopathic terrorists that are trying to kill us and we do have to realize that, whether we like it or not, they have already declared war on us,” Cameron said then. “There isn’t a ‘walk on by’ option. There isn’t an option of just hoping this will go away.”

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