President Barack Obama confirmed the death of the aid worker in what he called “an act of pure evil by a terrorist group that the world rightly associates with inhumanity.”
The announcement of Kassig’s death, the fifth such killing of a Western captive by the group, formed part of a 15-minute video posted online in which Islamic State showed the beheadings of at least 14 men it said were pilots and officers loyal to Syrian president Bashar al-Assad.
Kassig, 26, from Indiana, was also known as Abdul-Rahman, a name he took after converting to Islam in captivity. His parents have said through a spokesperson their son was taken captive on his way to the Syrian city of Deir al-Zor on October 1, 2013.
“Today we offer our prayers and condolences to the parents and family of Abdul-Rahman Kassig, also known to us as Peter,” Obama said in a statement to reporters on Air Force One as he returned to the United States from the G20 summit in Brisbane, Australia.
The video did not show the beheading of Kassig, who previously served in the US Army, but showed a masked man standing with a decapitated head covered in blood at his feet. Speaking in English in a British accent, the man says: “This is Peter Edward Kassig, a US citizen.”
The video appeared on a jihadist website and on Twitter feeds used by Islamic State.
Kassig’s parents, Ed and Paula Kassig, issued a statement saying: “We prefer our son is ... remembered for his important work and the love he shared with friends and family, not in the manner the hostage-takers would use to manipulate Americans and further their cause.”
The man in the video spoke with the same southern British accent as the killer of previous hostages, dubbed “Jihadi John” by British media. He was believed to have been wounded in an air attack on an IS leaders’ meeting in Iraq near the Syrian border earlier this month, some media reports have said.
French daily Le Figaro said on its website that the French Interior Ministry was studying the possibility of the presence of a French national among the Islamic State militants who beheaded Kassig.
In the video, a masked militant says: “To Obama, the dog of Rome, today we are slaughtering the soldiers of Bashar and tomorrow we will be slaughtering your soldiers,” in a prediction that Washington would send more troops to the region to fight Islamic State.
“And with Allah’s permission ... the Islamic State will soon ... begin to slaughter your people in your streets.”
The format of the video was different from previous such announcements, showing other beheadings in graphic detail, and also showing most of the killers unmasked. The purported location also was disclosed as the northern Syrian town of Dabeq.
An Islamic State supporter in Syria contacted by Reuters said: “The message is very clear. This is what the West understands. They think they can scare us with their planes and their bombs. No, not us. We are out to impose the religion of God and, by his will, we will.”
Kassig was doing humanitarian work through Special Emergency Response and Assistance, an organisation he founded in 2012 to help Syrian refugees, the family has said.
Obama said Kassig’s life stood in stark contrast to the values represented by Islamic State, adding he was a “humanitarian who worked to save the lives of Syrians.”