UK's Cameron vows 'full-spectrum response' after Tunisia beach attack

The number of Britons killed in a massacre at a resort Friday could climb as high as 30. The gunman, who was killed, posted support for Islamic State on Facebook page.

As the British death toll in Friday's beach gunman attack in Tunisia climbs to levels not seen since the July 2005 London bombings, Prime Minister David Cameron promised a "full-spectrum response" to combat extremism in Britain and abroad.

So far, the Foreign Office has confirmed 17 Britons among the 38 total killed Friday, when a lone gunman opened fire upon tourists at a resort beach. Three Irish citizens were also killed in the attack. Britain's Channel 4 reports that Foreign Minister Philip Hammond said that identifications were slowed because the victims were "dressed for the beach, not carrying ID physically on them."

"There are a significant number of victims who have not been positively identified at this time and it is highly likely that a significant proportion of them will be British," he said.

Officials warn the tally could climb as high as 30, reports the Associated Press. That would make it the worst terror attack on British citizens since the 2005 subway and bus attacks that killed 52 commuters.

The attacker, identified as Seifeddine Rezgui, a Tunisian student in his early 20s, was killed by police as he tried to escape the scene. The BBC reports that he was not known as an Islamic extremist by friends and family, who described him as polite, funny, and a fan of breakdancing. But the Telegraph writes that he posted support for the self-declared Islamic State on his Facebook page. And the Iraqi-Syrian terrorist group claimed that it had organized the attack, calling Rezgui by the nomme de guerre Abu Yahya al-Qayrawani.

The Christian Science Monitor's Dan Murphy writes that while "groups that rely on terror often claim attacks they didn't plot or execute to make themselves look more powerful," IS appears to have "supplanted Al Qaeda as the go-to brand for people seeking to murder in the name of Islam."

So far, IS has focused on capturing and ruling territory in Iraq and Syria. But given its expansive goals, apocalyptic beliefs, and limited conventional ability, a shift toward global terrorism looks like a foregone conclusion. And that makes more international attacks increasingly likely.

In a commentary published in The Sunday Telegraph, Mr. Cameron wrote that "we must do more to work together and build our capacity to deal with terrorism," singling out IS, also known as ISIL, in particular. He also wrote that IS was an enemy to Muslims as well as to the West, and that Britain would cooperate with Muslim countries to counter it.

To carry out an attack in the month when millions of Muslims are observing the holy month of Ramadan and to do so in the name of that faith is an insult to all Muslims worldwide.

We stand in solidarity with all communities who are affected and outraged by these events, and remain united in our determination not to let them divide us.

After all, this is not the war between Islam and the West that ISIL want people believe. It’s between the extremists who want hatred to flourish and the rest of the world who want freedom to prosper. They will kill anyone that doesn’t adhere to their warped worldview – Muslim and non-Muslim. They demonstrate that day in, day out.

Speaking to the BBC's Radio 4 today, he said that a response to IS would not necessarily entail the involvement of British ground forces. British planes have been supporting anti-IS forces in Iraq, but regular troops would be too far, he suggested. "Our strategy is to build up local armies. It's much easier to just invade a country ... it's easier and faster, but that has consequences."