ISIS extremists have posted a new video online showing the beheading of British aid worker Alan Henning.

The video footage, which lasts for just over a minute, was uploaded Friday evening online, according to The Sentinel. The video was entitled "Another Message To America and Its Allies", and showed Henning kneeling down beside a masked man with a knife, apparently his executioner.

In the video, the masked man made a statement directed towards British Prime Minister David Cameron, saying "The blood of David Haines was on your hands, Cameron. Alan Henning will also be slaughtered, but his blood is on the hands of the British Parliament."

The video, which was uploaded on YouTube and spread through pro-Islamic Twitter accounts, opened with a news report regarding the British government's decision to commence air strikes against jihadist elements in Iraq, reports SMH.

After the news report, the video then cuts to Henning, showing him kneeling down on the sand wearing orange-colored garb beside a masked man holding a knife. Henning reads from a script, saying, "Because of our parliament's decision to attack the Islamic State, I, as a member of the British public, will now pay the price for that decision."

Prime Minister David Cameron reacted to the ISIS video, says a UK Reuters article, saying that "the brutal murder of Alan Henning by ISIL shows just how barbaric and repulsive these terrorists are. My thoughts and prayers tonight are with Alan's wife Barbara, their children and all those who loved him."

"Alan had gone to Syria to help get aid to people of all faiths in their hour of need. The fact that he was taken hostage when trying to help others and [has] now [been] murdered demonstrates that there are no limits to the depravity of these Isil terrorists," added Cameron. "We will do all we can to hunt down these murderers and bring them to justice."