LONDON (CNN) — UK Prime Minister David Cameron said Saturday that the death of British aid worker Alan Henning at the hands of ISIS was “absolutely abhorrent” and “unforgivable.”
A short video released by ISIS on Friday appeared to show Henning’s beheading, with the killer blaming the death on the United Kingdom for joining the U.S.-led bombing campaign against the group.
In response, Cameron said Britain must work with its allies to do “everything it can” to defeat ISIS in the region and at home, and vowed to “use all assets we have” to help other hostages and their families.
“What we see with this organization is there’s no level of depravity to which they will not sink. No appeals made any difference,” he said, speaking at the Prime Minister’s country house retreat, Chequers.
“The fact this was a kind, gentle, compassionate and caring man who had simply gone to help others, the fact they murdered him in the way they did, shows what we are dealing with, and this is going to be our struggle there. With others, we must do everything we can to defeat this organization,” Cameron said.
“We must take action against it. We must find those responsible.”
But he warned that the struggle against the “barbaric” group, also known as ISIL and which calls itself the Islamic State, would not be quick. He said it would take “patience, hard work and resolve to defeat this group — but I know in this country we have that resolve.”
The Prime Minister said he had held briefings with senior military and intelligence advisers, as well as with the head of the Home Office and others, “to make sure we do everything that we can, whether that is taking down these hateful videos from the Internet, whether it’s stopping preachers of hate, whether it’s prosecuting those who glorify terrorism, whether it’s working with others to defeat ISIL in the region.”
He added, “Everything we can do, we will do.”
A taxi driver from near Manchester in northern England, Henning was part of a team of volunteers who traveled to Syria in December 2013 to deliver aid to people affected by the country’s devastating civil war. He was abducted by masked gunmen the day after Christmas, other people in the aid convoy said.
‘Our local and national hero’
At a ceremony at Manchester Central Mosque on Saturday, a joint statement mourning the loss of Henning was read out on behalf of mosques throughout the north of England.
“Alan Henning was our local and national hero,” it said. “We will remember him as a tireless and selfless volunteer aid worker whose only concern was to help people in need.
“We send our heartfelt condolences to Alan Henning’s family and what must be an unbearable time.
“The killing of Alan Henning was a cowardly and criminal act of appalling brutality by a group who do not represent Islam at all and in fact are an insult to the Islamic faith.”
Some 200 mosques and organizations put their names to the joint statement, together representing about a million people, according to mosque officials.
Cameron also said Henning would be mourned by his many Muslim friends, as well as the whole country. Henning was 47, according to UK media reports.
The news of Henning’s beheading came just days after Britain joined the U.S.-led coalition against ISIS, following overwhelming approval from Parliament.
UK jets began flying reconnaissance flights over Iraq a week ago, and on Tuesday dropped their first missiles on an ISIS heavy-weapon position and an armed pickup truck in Iraq, according to the UK Defense Ministry.
The White House released a statement condemning Henning’s murder and vowing to work alongside the United Kingdom and its allies to “degrade and ultimately destroy ISIL.”
Henning appears to be the fourth Westerner to be beheaded on camera by ISIS.
This summer, ISIS beheaded American freelance 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.
Last week, the British Foreign Office released an audio file of Henning pleading for his life.
His wife, Barbara Henning, made a public plea for ISIS to spare his life — an appeal joined by voices of Muslim leaders around the world. But their pleas were ignored.
At the end of the video released Friday, ISIS shows American aid worker Peter Kassig and threatens his life.
UK Muslim group ‘disgusted’
Talha Ahmad, a spokesman for the Muslim Council of Britain, told CNN on Saturday that the organization was “devastated and disgusted” by Henning’s murder, which he called “the latest round of despicable violence by ISIS.”
Ahmad said that it “should really cause anyone who has the slightest sympathy for ISIS to recognize that the timing, the method, the mechanism and the target that they have chosen in this latest incident shows that they do not stand for Islam or represent any strand of Islam, but a perverted version of cruelty, inhumanity, inflicted to maximize propaganda for their needs.”
Ahmad said the murder confirmed that ISIS is “not a religiously inspired organization” but rather a militia group “hell-bent on inflicting pain and cruelty.”
He does not believe a very large number of people sympathize or are even prepared to tolerate the kind of attitude shown by ISIS, he said.
“The challenge we have is to make the case again and again that however tempting, however lucrative it may appear to support a group which stands up to the Western ‘bully,’ if you like, the reality is ISIS do not represent a hope,” he said.
One heartening thing to come out of the tragedy of Henning’s death, he said, is that “Muslims world over, certainly in the UK, of all shades and colors and theology, have come together to condemn ISIS and we just need to keep doing that.”
UK authorities believe at least 500 British citizens have gone to Iraq and Syria, many of them to fight with ISIS and other Islamist groups — and that most will try to return, bringing their extremist views with them.
Cameron last month laid out new measures to tackle the threat posed by would-be UK jihadists, days after Britain raised its terror threat level from “substantial” to “severe.”
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