Peter Kassig Beheading Video: Jihadi John Leads Gruesome Execution of American Aid Worker along with 16 Syrian Soldiers

Another ISIS video, which showed American aid worker Peter Kassig being beheaded, shocked the world on Sunday. The gruesome video shows a systematic execution of the American citizen, along with the beheading of over 16 regular army soldiers.

This is the first ISIS video that shows the black-clad and masked extremist known as 'Jihadi John' leading two different beheadings.

While he stood over the severed head of American aid worker, who is also known by his Islamic name Abdul Rahman Kassig, the British jihadist killer also appears in a graphic mass beheading in the earlier parts of the video.

The graphic 15-minute video, which was initially published by Al-Furqan media – the Islamic State's media and propaganda organisation -- and shared via several ISIS-affiliated social media accounts, showed the British national, Jihadi John, standing over a severed head.

"The head is that of Peter Edward Kassig, a US citizen of your country, who fought against the Muslims in Iraq while serving as a soldier in the American army," the black clad hardliner militant is heard saying in a speech addressed to US president Barack Obama.

The executed men were shown wearing matching blue uniforms and were led in a line. Each prisoner was dragged by an Islamic State fighter.

All other executors, except Jihadi john, are seen wearing masks and appear to be clad in khaki desert fatigues. Each militant drags his victim in a line before bringing out black knives from a nearby wooden box.

After being forced to walk along a line in what appears to be an arid terrain – as shown in other ISIS beheading videos – they are ordered to bend down on the ground in front of their respective executors.

Jihadi John stands in the middle of the line with his own victim kneeling before him. This is the first time the notorious man is seen beheading prisoners from the Assad army, rather than journalists or foreign aid workers.

"To Obama, the dog of war. Today we are slaughtering the soldiers of Bashar and tomorrow we will slaughter your soldiers," declares Jihadi John in a wicked voice.

"With Allah's permission, we will break this final and last crusade and the Islamic State will soon, as your puppet David Cameron said, begin to slaughter your people on your streets."

Close-ups are used to show the terrified expressions of the victims. A single word order of Jihadi John in Arabic nudges the Islamic State fighters in action with all of them starting to execute the systematic and meticulously planned mass murder.

They force their victims to lie flat on the ground, before pulling their heads to expose their necks in front of the camera. Jihadi John gets a close-up of the camera as every fighter begins their gruesome activity of cutting off the heads of their respective victims in what looks like a precisely synchronised mass beheading.

As the victims' bodies writhe in pain Jihadi John peers at the camera with an organised film-making technique in place.

The horrifying episode is concluded by showing close-up shots of the beheading before a final shot, which shows all the dead victims lying in a line.

The beheading job is finished off with a dramatic concluding voice-over from Islamic State's leader Abu Bakr al-Baghdadi, who says in a pompous expression: "Know that we have armies in Iraq and an army in Sham (Syria) of hungry lions whose drink is blood and play is carnage."

Although the exact location of the video is unknown, there are speculations that it could be Dabiq, the symbolic place for ISIS, which was earlier referred to as the place where the Armageddon will begin, in accordance to the Hadith.

The identities of the executioners are not yet confirmed, although one of them is believed to be a French fighter known by the name Abu Abdullah al-Firansi.

Unlike in previous videos showing the killings of the US journalist Fames Foley and Steven Sotloff as well the British aid workers David Haines and Alan Henning, the latest footage does not show Kassig alive in the beginning of the video.

The new video also does not include the threat to kill the "next hostage".

Kassig, who served in Iraq in 2007 and 2013 travelled to Syria as an aid worker, was captured and taken hostage by the notorious jihadist group in October last year. The militants had threatened to behead him in another video showing the murder of the British aid worker Alan Henning over a month ago.