BEIRUT (PIX11/AP) — An Internet video purports to show the beheading of U.S. journalist Steven Sotloff by the Islamic State group.
According to a family spokesman, Sotloff's relatives are aware of the beheading video and are grieving.
Sotloff, who freelanced for Time and Foreign Policy magazines, had last been seen in Syria in August 2013 until he appeared in a video released online last month by the Islamic State group that showed the beheading of fellow American journalist James Foley.
Intelligence officials continue to investigate Foley's alleged killer, suspected to be a British rapper-turned-jihadist named Abdel-Majet Abdel Bary.
Dressed in an orange jumpsuit against the backdrop of an arid Syrian landscape, Sotloff was threatened in that video with death unless the U.S. stopped airstrikes on the group in Iraq.
In the video distributed Tuesday and entitled "A Second Message to America," Sotloff appears in a similar jumpsuit before he is beheaded by an Islamic State fighter.
News of the video appears to have been broken by Site Intelligence Group, which reports on actions by jihadist groups. In the same tweet the group claims that the group is now threatening to execute Briton David Cawthorne Haines.
Before Foley was killed, the extremist group holding him captive demanded $132.5 million or the release of Muslim prisoners in exchange for Foley's freedom, according to the GlobalPost.
There was not much negotiation on the part of Foley's captors, who made limited demands via email, according to GlobalPost President and Chief Executive Philip Balboni.
Over the July 4th holiday weekend, U.S. special forces attempted to rescue Foley, Sotloff and others held hostage in Syria. Intelligence led the team of commandos to to an area outside the ISIS stronghold Raqqa -- but no hostages were found.