An Internet video released Friday purports to show an Islamic State group fighter beheading British hostage Alan Henning and threatening yet another American captive, the fourth such killing carried out by the extremist group now targeted in US-led airstrikes.
The video mirrored other beheading videos shot by the Islamic State group, which now holds territory along the border of Syria and Iraq. It ended with an Islamic State fighter threatening a man they identified as an American.
"Obama, you have started your aerial bombardment of Shams (Syria), which keeps on striking our people, so it is only right that we continue to strike the neck of your people," the masked militant said.
The Associated Press could not immediately verify the video's authenticity, though it was released in the same manner as other Islamic State group videos and the masked militant sounded similar to the one who carried out the other slayings.
The British Foreign Office said: “We are aware of the video and are working urgently to verify the contents. If true, this is a further disgusting murder. We are offering the family every support possible; they ask to be left alone at this time.”
Prime Minister David Cameron said the "brutal murder" of aid worker Alan Henning by Islamic State "shows just how barbaric and repulsive these terrorists are", and vowed to "do all we can to hunt down these murderers and bring them to justice".
Labour leader Ed Miliband said: "The murder of Alan Henning by ISIL is appalling and barbaric. He was an aid worker, helping those in need. Those who killed him have revealed only their lack of humanity and brutality. My thoughts and deepest condolences are with his wife Barbara, his children and all those who knew him. We will do everything we can to support the efforts of the Government to bring those guilty of this terrible act to justice."
This is the fourth such video released by the Islamic State group. The full beheadings are not shown in the videos, but the British-accented, English-speaking militant holds a long knife and appears to begin cutting the three men, American reporters James Foley and Steven Sotloff and British aid worker David Haines.
Henning, 47, nicknamed "Gadget," had joined an aid convoy and was taken captive on Dec. 26, shortly after crossing the border between Turkey and Syria. Earlier this week, Henning's wife Barbara Henning asked the militants in a televised plea: "Please release him. We need him back home."
Dozens of Muslim leaders in Britain have urged the Islamic State group to release Alan Henning. His wife had said she had been given hope by "the outcry across the world" over her husband's imprisonment.