IS Beheads US Journalist James Foley In Video

Islamic State militants have released a video that shows the beheading of a US journalist who went missing two years ago.

The footage shows a masked man - speaking in English with an English accent - killing James Foley, who was seized by armed men in Syria in November 2012.

In the five-minute propaganda video, posted on social media sites by Islamic State sources, the man says Mr Foley was being killed because Barack Obama had ordered airstrikes against IS positions in northern Iraq.

Just hours after the video was released, a US official said American drones had carried out nearly a dozen airstrikes in Iraq since Tuesday.

The journalist, dressed in an orange jumpsuit like those worn by Guantanamo inmates, is seen kneeling in the desert before he blames the US for his death, in a statement presumably prepared by his abductors.

He then says: "I wish I had more time, I wish I could have the hope of freedom and seeing my family once again, but that ship has sailed."

He is then beheaded.

The group also claimed to be holding another American journalist, Steven Sotloff, who appears at the end of the video, and said his life depended on the US President's next move.

On Wednesday, the FBI said it believed the video to be authentic.

British Foreign Secretary Philip Hammond said the video, voiced by an IS fighter with a British accent, was "an appalling example of the brutality of this organisation".

Speaking on Wednesday morning, Mr Hammond said: "All the hallmarks point to it being genuine".

When asked whether he acknowledged the killer's British accent, he said: "Certainly at first pass that's what it looks like and we will obviously want to investigate that further."

The Foreign Secretary also told Sky News later he did not believe the US would be "cowed" by IS threats to kill US journalist Steven Sotloff, who they claim to be holding.

A statement issued by Mr Foley's mother, Diane Foley, said: "We have never been prouder of our son, Jim. He gave his life trying to expose the world to the suffering of the Syrian people.

"We implore the kidnappers to spare the lives of the remaining hostages. Like Jim, they are innocents. They have no control over American government policy in Iraq, Syria or anywhere in the world.

"We thank Jim for all the joy he gave us. He was an extraordinary son, brother, journalist and person. Please respect our privacy in the days ahead as we mourn and cherish Jim."

According to witnesses, Mr Foley was seized in the northern Syrian province of Idlib on November 22, 2012.

His family had not heard from him since, despite a public campaign for information.

Several senior US officials with direct knowledge of the situation told the Associated Press that IS very recently threatened to kill Mr Foley to avenge the American airstrikes over the last two weeks.

The strikes targeted militants advancing on Mount Sinjar, the Mosul Dam and Kurdish capital Irbil.

Prime Minister David Cameron returned to Downing Street from his holiday early after the beheading, which came just days after he warned Europe could be facing a "poisonous" terrorist state on its doorstep.

The release of the video comes a day after IS militants threatened to attack US targets in another video where they warned "we will drown all of you in blood".