ISIS has released a video showing another beheading, that of a British aid worker, David Haines, the father of two who went to Syria to serve at a refugee camp. The terrorist group says the execution, which has evoked a strong global condemnation including from President Obama, is "a message to the allies of America."
"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," British Prime Minister David Cameron tweeted early Sunday, the day after the video was released by the Islamic State, or ISS, Saturday night.
The gruesome video looks similar to the two previous videos showing the beheading of U.S. journalists James Foley and Steven Sotloff, and threatens to kill another British hostage.
"I would like to declare that I hold you David Cameron entirely responsible for my execution," 44-year-old Haines can be heard saying in the video. "You entered voluntarily into a coalition with the United States against the Islamic State just as your predecessor Tony Blair did, following a trend against our British prime ministers who can't find the courage to say 'no' to the Americans."
The masked executioner then speaks with a British accent. "This British man has to pay the price for your promise, Cameron, to arm the Peshmerga [Kurdish] against the Islamic State. If you, Cameron, persist in fighting the Islamic State then you like your master Obama will have the blood of your people on your hands."
In the last video showing the execution of U.S. journalist Sotloff, ISIS had threatened to kill Haines, who was working for a French international aid agency, ACTED, when he was abducted last March in Atmeh, Syria.
"We will do everything in our power to hunt down these murderers and ensure they face justice, however long it takes," said Cameron, who was due to chair an emergency meeting Sunday.
President Obama also condemned the execution. "The United States strongly condemns the barbaric murder of U.K. citizen David Haines by the terrorist group ISIL," he said in a statement late Saturday. "Our hearts go out to the family of Mr. Haines and to the people of the United Kingdom. The United States stands shoulder to shoulder tonight with our close friend and ally in grief and resolve."
ISIS, also known as ISIL or Islamic State of Iraq and Syria, is an al-Qaeda offshoot, which wants to form an Islamic emirate in the Levant region through "jihad."
Obama added that the U.S. will work with the U.K. and a broad coalition of nations from the region and around the world "to bring the perpetrators of this outrageous act to justice, and to degrade and destroy this threat to the people of our countries, the region and the world."
On Friday, the White House and the Pentagon said for the first time that the United States is "at war" with ISIS.
A statement released by the U.K.'s Foreign Office, which is working to verify the video, quoted the victim's brother, Mike Haines, as saying that he "was and is loved by all his family."
"David was most alive and enthusiastic in his humanitarian roles. His joy and anticipation for the work he went to do in Syria is for myself and family the most important element of this whole sad affair," the brother said.
Australian Prime Minister Tony Abbott said the execution was "further demonstration that this particular terrorist group does not just do evil, but exults in doing evil."
"The heinous murder of David Haines shows once again how the international community must mobilize against Daesh," the French presidency said in a statement.
Scottish First Minister Alex Salmond said the murder "demonstrated a degree of brutality which defies description."
According to the CIA, ISIS has about 31,500 fighters across Iraq and Syria.
ISIS men have killed hundreds of civilians in Iraq. Numerous members of the Christian and Yazidi minorities have also been killed, and tens of thousands of them have fled their homes.