Thirty-eight people — mostly British, but also including a Belgian and a German — were killed when the 23-year-old killer, Seifeddine Rezgui went on a rampage outside the Imperial Marhaba hotel in Tunisia. Police are Monday seeking up to two accomplices to the shooting, which has left the UK with its biggest terrorism death toll since the 7/7 London bombings of 2005.
UK Police have dispatched 600 police to speak to survivors both in Tunisia and the UK, as the victims continue to be identified and survivors are treated in hospital. Cameron called for a "full-spectrum response — a response at home and abroad; in the immediate aftermath and far into the future.
"We will not be cowed. To our shock and grief we must add another word: resolve. Unshakeable resolve. We will stand up for our way of life. Across the world, we must do more to work together and build our capacity to deal with terrorism."
"ISIL may use ancient barbarism in its methods of killing, but it is modern in its propaganda techniques, using social media as its primary weapon. We must also deal with it at its source, in places like Syria, Iraq and Libya, from where ISIL is peddling and plotting its death cult," Cameron wrote in the Daily Telegraph.
In a BBC interview on Monday, he said the world needed to unite and take on ISIL which declared a caliphate exactly a year ago on June 29, 2014. "It's not an 'Islamic State'. It's an appalling barbarous regime. It is a perversion of the religion of Islam and the creation of this poisonous death cult that I seducing too many young minds in America, the Middle East and elsewhere," he said.
"This is, I think, going to be the struggle of our generation and we have to fight it with everything we can."
"Full Spectrum Response"
UK North Africa Minister Tobias Ellwood confirmed at least 15 British nationals had been killed in the attack, and warned the number might rise. A Crisis Centre has been mobilized along with a Rapid Deployment Team designed to provide urgent UK assistance in Tunisia and the UK.
I have asked for the flags over No10 to be flown at half-mast in memory of the victims of the terrorist attack in Tunisia.— David Cameron (@David_Cameron) June 28, 2015
Cameron said there needed to be a long-term international response to ISIL and its radicalization of young people. He told the BBC: "Our system of values of democracy, freedom, fairness and tolerance is so much greater that their system of value. You have to have a full spectrum response. Yes, of course, you have to crush ISIL in Iraq and Syria.
"Squeezing it is not enough. We have to deal with this appalling radical narrative that's taking over the minds of so many young people in our own country."