By Mariano Castillo
(CNN) — [Breaking news update at 6:20 p.m. ET]
The White House released a statement Friday condemning the beheading of UK citizen Alan Henning by ISIS, also referred to as ISIL.
“Mr. Henning worked to help improve the lives of the Syrian people and his death is a great loss for them, for his family and the people of the United Kingdom,” the statement said.
“Standing together with our UK friends and allies, we will work to bring the perpetrators of Alan’s murder — as well as the murders of Jim Foley, Steven Sotloff and David Haines — to justice. Standing together with a broad coalition of allies and partners, we will continue taking decisive action to degrade and ultimately destroy ISIL.”
[Breaking news update at 6:12 p.m. ET]
The parents of Peter Kassig confirmed Friday that their son, “who was doing humanitarian work in Syria, is being held captive.” The family did not offer any other information. Kassig, an American aid worker, is shown on an ISIS video that purports to show the beheading of British aid worker Alan Henning.
[Original story published at 5:46 p.m. ET]
A short video released by ISIS on Friday shows the apparent beheading of British aid worker Alan Henning.
Before he is killed, Henning speaks to the camera, referencing the British Parliament’s decision to join the bombing campaign against ISIS. At the end of the video, ISIS shows an American aid worker, Peter Kassig, and threatens his life.
There is no reason to believe that the video is not authentic, a U.S. intelligence official told CNN, adding that U.S. officials are studying it.
A taxi driver from near Manchester, England, Alan Henning was part of a team of volunteers that traveled to Syria in December 2013 to deliver food and water to people affected by the Middle Eastern country’s devastating civil war.
He was abducted the day after Christmas by masked gunmen, according to other people in the aid convoy.
“The brutal murder of Alan Henning by ISIL shows just how barbaric and repulsive these terrorists are,” UK Prime Minister David Cameron said, referring to the terror group also known as ISIL.
“Alan had gone to Syria to help get aid to people of all faiths in their hour of need,” Cameron said. “The fact that he was taken hostage when trying to help others and now murdered demonstrates that there are no limits to the depravity of these ISIL terrorists.”
The Prime Minister vowed to bring the killers to justice.
Last week, the British Foreign Office released an audio file of Henning pleading for his life. His wife made a public plea for ISIS to spare his life.
Barbara Henning’s pleas were joined by voices of Muslim leaders around the world.
They included Shaykh Haitham Al Haddad, a judge on the Shariah Council in London, who has said that “whatever your grievance with American or British foreign policy, executing this man is not the answer.”
But the calls for mercy appear to have been met with bloodshed. If the authenticity of the video is confirmed, Henning will be the fourth Westerner to be beheaded on camera by ISIS.
This summer, ISIS beheaded American journalists James Foley and Steven Sotloff — showing their gruesome killings in videos posted online. ISIS then claimed its first British victim, aid worker David Haines, according to video that appeared online on September 13.
In the video released by ISIS Friday, Henning’s name is misspelled “Allen.”
Henning’s beheading comes shortly after Britain joined the U.S.-led military effort against ISIS targets in Iraq and Syria.
British jets began flying reconnaissance flights over Iraq a week ago, and on Tuesday dropped its first missiles on an ISIS heavy-weapon position and an armed pickup truck in Iraq, according to the UK Defense Ministry.
The American who appears at the end of the video, Kassig, is a former soldier who became an aid worker in the Middle East.
Tattooed and pale, with an Arabic vocabulary of a few dozen words at best, the sight of Kassig treating wounded Syrians in a Lebanese hospital — where CNN profiled him in 2012 — might have seemed out of place.
How did an American end up in a Lebanon hospital treating wounded Syrians from months of escalating violence?
Kassig’s journey began when he joined the U.S. Army in 2006 and deployed to Iraq in 2007. He was honorably discharged for medical reasons after a brief tour and returned to the United States to study political science and train for 1,500-meter runs. But something wasn’t right, he told CNN in 2012.
He decided he would head to Beirut, follow the situation in Syria and try to help.
The details surrounding his kidnapping were unclear.
CNN’s Arwa Damon, Brian Todd and Chelsea J. Carter contributed to this report.
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