Islamic State extremists have posted a video purportedly showing the beheading of British aid worker David Haines, who went missing in Syria last year.
The video appears to be intended as a threat to countries supporting military action in the Middle East, according to news reports.
It emerged hours after the family of Haines issued a public plea late Friday urging his captors to contact them.
The two-and-a-half-minute video includes what appears to be a threat directed at British Prime Minister David Cameron.
“For being a lapdog, Cameron, you will drag your people into another bloody and unwinnable war,” the video warns.
Cameron responded on Twitter to the video, writing: “The murder of David Haines is an act of pure evil. My heart goes out to his family who have shown extraordinary courage and fortitude. … We will do everything in our power to hunt down these murderers and ensure they face justice, no matter how long it takes.”
The British Foreign Office said late Saturday it was “working urgently to verify” the video.
“If true, this is another disgusting murder,” the Foreign Office said. “We are offering the family every support possible. They ask to be left alone at this time.”
Haines, 44, a father of two, was abducted by Islamic State in Syria in March 2013 while working for an international aid agency.
The British government kept his kidnapping secret out of concern for his safety until the most recent video identified him as a captive.
Late Friday, Haines’ family had issued a public plea, in a short statement released through Britain’s Foreign and Commonwealth Office, saying, “We are asking those holding David to make contact with us.”
Islamic State militants previously have beheaded two American journalists in the past month, James Foley and Steven Sotloff, as well as Kurdish and Lebanese fighters, and posted videos online showing the killings.
At the end of the last video, showing the beheading of Sotloff, the Islamic State group threatened to kill Haines next and briefly showed him on camera.
In the video posted Sunday, the group threatened to kill another Briton. Both British men were dressed in orange jumpsuits against an arid Syrian landscape, similar to that seen in the Foley and Sotloff videos.
The SITE Intelligence Group, a U.S. terrorism watchdog, reported the video, which was also posted online by users associated with the Islamic State group.
The video was entitled “A Message to the Allies of America.” Haines’ purported killer, who appeared to be the same man speaking with a British accent as in the previous videos, tells the British government that its alliance with the United States will only “accelerate your destruction” and will drag the British people into “another bloody and unwinnable war.”
In the Foley and Sotloff videos, the insurgent group warned President Barack Obama there would be consequences if the United States doesn’t stop air strikes against it in Iraq.
Obama laid out a four-part plan Wednesday that includes going after Islamic State in Syria. In his speech that day, the president said he is prepared to order air strikes in Syria and send in 475 military advisers.
“I have made it clear that we will hunt down terrorists who threaten our country, wherever they are,” said Obama, who vowed not to send combat troops to the region.
Source: Chicago SunTimes