Islamic State insurgents who released a video of an American journalist being beheaded say the life of another reporter depends on US action in Iraq.

The FBI believes the footage is authentic.

It shows James Foley who went missing in Syria two years ago being murdered by an extremist with a British accent.

The group claims the killing was retaliation for U.S. air strikes in Iraq.

In the video they threaten the life of another American journalist Steven Sotloff.

Irish Times Foreign Affairs Correspondent Mary Fitzgerald says she'd warned him of the dangers...