Update 6 p.m. EST: Kassig's parents released a statement, saying they are "heartbroken." "Abdul-Rahman Peter Kassig, has lost his life as a result of his love for the Syrian people and his desire to ease their suffering," Ed and Paula Kassig said, according to CNN.

Original post:

The White House has confirmed that a video showing the execution of Peter "Abdul-Rahman" Kassig, a former U.S. Army Ranger captured by the Islamic State group, is authentic. President Barack Obama issued a statement, expressing condolences to Kassig's family and condemning the group responsible.

"Abdul-Rahman was taken from us in an act of pure evil by a terrorist group that the world rightly associates with inhumanity," Obama said. "Like Jim Foley and Steven Sotloff before him, his life and deeds stand in stark contrast to everything that ISIL represents."

Kassig, 26, who was working with refugees in Syria at the time of his kidnapping, changed his first name to Abdul-Rahman when he converted to Islam during his captivity.

The video was posted online early Sunday and differs from those posted following the executions of Foley, Sotloff and two Britons. It depicts members of the Islamic State group beheading Kassig in an area that a man on the video identifies as Syria. Sky News reports that the video also appears to show a militant known as Jihadi John, who is said to be responsible for previous hostage beheadings and was believed injured after a recent U.S. airstrike targeted senior Islamic State members.

The clip is more than 15 minutes long. It shows a dozen or more other men also being beheaded. They are identified by the masked man in the video as Syrian officers and pilots from Bashar Assad's forces, Al-Jazeera reported. The masked man also identifies Kassig by name.

Kassig founded a group to help Syrian refugees called Special Emergency Response and Assistance after serving with U.S. forces in Iraq in 2007. He was detained in Syria more than a year ago.

Below is the full White House statement.

Today we offer our prayers and condolences to the parents and family of Abdul-Rahman Kassig, also known to us as Peter. We cannot begin to imagine their anguish at this painful time.

 Abdul-Rahman was taken from us in an act of pure evil by a terrorist group that the world rightly associates with inhumanity. Like Jim Foley and Steven Sotloff before him, his life and deeds stand in stark contrast to everything that ISIL represents. While ISIL revels in the slaughter of innocents, including Muslims, and is bent only on sowing death and destruction, Abdul-Rahman was a humanitarian who worked to save the lives of Syrians injured and dispossessed by the Syrian conflict.  While ISIL exploits the tragedy in Syria to advance their own selfish aims, Abdul-Rahman was so moved by the anguish and suffering of Syrian civilians that he traveled to Lebanon to work in a hospital treating refugees. Later, he established an aid group, SERA, to provide assistance to Syrian refugees and displaced persons in Lebanon and Syria.  These were the selfless acts of an individual who cared deeply about the plight of the Syrian people.  

ISIL's actions represent no faith, least of all the Muslim faith which Abdul-Rahman adopted as his own.  Today we grieve together, yet we also recall that the indomitable spirit of goodness and perseverance that burned so brightly in Abdul-Rahman Kassig, and which binds humanity together, ultimately is the light that will prevail over the darkness of ISIL.