The White House says it has determined that a video showing the brutal killing of freelance journalist Steven Sotloff is authentic.
Islamic State extremists released the video showing Sotloff's beheading on Tuesday. It comes two weeks after the militants released a video showing the killing of James Foley, another American journalist.
In the Sotloff video, a masked militant warns President Barack Obama that continuing airstrikes against the group in Iraq will be met with the killing of more Western captives.
``I'm back, Obama, and I'm back because of your arrogant foreign policy toward the Islamic State ... despite our serious warnings,'' the fighter says. ``So just as your missiles continue to strike our people, our knife will continue to strike the necks of your people.''
Sotloff is a 31-year-old Miami-area native who freelanced for Time and Foreign Policy magazines. He vanished in Syria in August 2013.
In the video, the organization threatens to kill another hostage, this one identified as a British citizen. The U.S. National Security Council said Wednesday that the video was authentic
National Security Council spokeswoman Caitlin Hayden announced the U.S. intelligence community's assessment of the video in a statement Wednesday.
State Department spokeswoman Jen Psaki said Tuesday that ``a few'' Americans are believed to be held by the Islamic State.
Psaki would not give any specifics, but one is a 26-year-old woman kidnapped while doing humanitarian aid work in Syria, according to a family representative who asked that the hostage not be identified out of fear for her safety.
President Barack Obama says Americans will not be intimidated by the ``horrific'' violence of Islamic State militants after the beheading of a second U.S. journalist.
The president is vowing that ``justice will be served'' after the U.S. verified the authenticity of a video of freelance reporter Steven Sotloff's killing.
Obama said at a news conference while travelling Wednesday in Estonia that their deaths only unite Americans. He says Americans will not forget and the country's reach is long.