The White House on Wednesday morning confirmed that an Islamic State video showing the beheading of an American journalist is authentic.

“The U.S. intelligence community has analyzed the recently released video showing U.S. citizens James Foley and Steven Sotloff. We have reached the judgment that this video is authentic. We will continue to provide updates as they are available,” said National Security Council spokeswoman Caitlin Hayden.

President Obama will make a statement on Foley’s slaying early Wednesday afternoon.

Meanwhile, the Washington Post reports that U.S. and British intelligence officials are trying to identify the executioner in the video. He has a British accent, and linguistics experts and other analysts are trying to compare it to former Guantanamo Bay prisoners and British residents believed to have joined the Islamic State.