British Prime Minister David Cameron was on a summer holiday when news of the beheading of American journalist James Foley sparked an international search for the man with a British accent who decapitated the newsman. Mr Cameron cut short his vacation and lead the hunt for the jihadist.
The militant who goes by the name John is believed to be the leader of a group fighters born in Britain and had previously held hostages for the ISIL in Syria. A former hostage said John is the ringleader of a group referred to as The Beatles because of their British nationality.
The PM, after viewing the video of the beheading that went viral, acknowledged that based on what he saw and heard, particularly the English accent of the decapitator, it appears that John is a UK citizen.
"This is deeply shocking. But we know that far too many British citizens have travelled to Iraq and travelled to Syria to take part in extremism and violence ... And what we must do is redouble all our efforts to stop people from going," The Guardian quoted Mr Cameron.
As an initial step, he said Britain would cancel the passports of Britons who plan to travel to the Middle East to join the jihad as well as arrest and prosecute UK-born militants who are part of the ongoing extremism and violence.
There had actually been previous attempts by the US Special Operations force to rescue several Americans held by the extremist groups in Syria, including Foley, but the tries failed, said Obama administration officials.
The operations include drones and fighter jets circling the area overhead, but small-arms fire greeted the US troops upon landing. The American soldiers fired back and killed several fighters of the Islamic state, the officials disclosed.
However, after failing to find the hostages, they pulled out of the area.
Like Mr Cameron, US President Barack Obama was also on his summer holiday in Martha's Vineyard when news of the beheading erupted. In a statement, he said, "One thing we can all agree on is a group like ISIL has no place in the 21st century ... From governments and people across the Middle East, there has to be a common effort to extract this cancer so that it does not spread. There has to be a clear rejection of these kind of nihilistic ideologies."
Mr Cameron joined Mr Obama in speaking against the killing, saying, "Let me condemn the barbaric and brutal act that has taken place and let's be clear what this act is - it is an act of murder, and murder without any justification."
In Canberra, Australian Prime Minister Tony Abbott told Brisbane Radio 4BC, "It's absolutely sickening, absolutely despicable and it's a sign that there can be no compromise whatsoever with the murderous terrorists of the ISIL movement.