From the White House:

Office of the Press Secretary

The United States strongly condemns the barbaric murder of UK citizen David Haines by the terrorist group ISIL. 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. We will work with the United Kingdom 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.

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