Washington: In another gruesome video released on Sunday, the barbaric extremist group Islamic State has claimed the beheading of 26-year-old American aid worker Peter Kassig, reports said.
The 16-minute video released on social media purportedly shows a masked Islamic State fighter dressed in black standing near a severed head, that he claims to be that of Kassig.
The video also shows the mass execution of over a dozen and half captured Syrian troops, reports add.
The fighter wearing the same balaclava outfit donned by Jihadi John in previous videos, says, "This is Peter Edward Kassig, a US citizen of your country".
"Here, we are burying the first American crusader in Dabiq, eagerly waiting for the remainder of your armies to arrive," the militant added.
If the video's authenticity is confirmed, Kassig will be the fifth Westerner and third American to be beheaded by the ISIS in less than three months.
The beheading video comes more than a month after the IS released the beheading video of British aid worker Alan Henning in October. At the end of the video, the executioner - supposedly “Jihadi John” - had threatened to kill Peter Kassig, brandishing knife near his neck.
A day after the video release, Kassig's parents who hail from Indiana, took to YouTube to make an elegiac plea to the barbaric fighters, calling on them to show mercy and let their son go unharmed.
In the emotional video, Kassig's mother is shown wearing a headscarf and refers to her son as as Abdul-Rahman - a name he took after being converted to Islam during the IS captivity.
Kassig's parents made the request to the IS even as earlier pleas made by the parents of other hostages have fallen on Islamic State's deaf ears and the extremists have ended up beheading them.
His parents had also made public a letter written by Kassig in June, in which the twenty six-year-old American aid worker wrote how he was “pretty scared to die”, but still felt relieved that he tried to alleviate the sufferings of those in need.
"This is the hardest thing a man can go through, the stress and fear are incredible," wrote Kassig.
"Don't worry Dad, if I do go down, I won't go thinking anything but what I know to be true. That you and mom love me more than the moon and the stars."
He ended the letter with a heart-breaking "I love you."
Kassig had been held in Syria since October 2013. Kassig was an American Army Range before he went to the middle East to work as an aid worker in Syria.
Peter Kassig's first trip to the Middle East was as a US soldier , but later he became a medical worker to alleviate the sufferings of war victims.
Kassig had founded a relief organisation named Special Emergency Response and Assistance (SERA), and was working for the same when he was captured on his way to Deir Ezzor in eastern Syria last October.
The new IS video comes as the US and other anti-IS nations have intensified the air strikes against the Islamic State in Syria.
The video also may be the Islamic state's answer to the reports that claim that Jihadi John – the British-accented executioner was hit in US air strike.
Earlier there were reports of IS Caliph being injured in one of the air strikes by US-led anti-IS coalition.