Memorial service held for IS victim Steven Sotloff

Nearly 1,000 mourners including relatives, friends and politicians, have attended a memorial service in Florida for US journalist Steven Sotloff, who was killed by IS militants.

The Islamic State released a video on Tuesday showing the murder of Mr Sotloff.

He is the second American journalist to be beheaded in two weeks over the group's confrontation with the US over air strikes in Iraq and its foreign policy.

Footage of James Foley being beheaded on August 19 shocked the world.

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Cameron and Obama will 'not to be cowed' by IS

David Cameron and Barack Obama have vowed to confront the militant group Islamic State (IS).

In a joint article in The Times (£), the leaders said the UK and US could "not be cowed by barbaric killers", claiming those who want to adopt an "isolationist approach" do not understand the threat faced.

David Cameron and Barack Obama say Britain and America Credit: Reuters

"Developments in other parts of the world, particularly in Iraq and Syria, threaten our security at home," they wrote.

"We will not waver in our determination to confront Isil. If terrorists think we will weaken in the face of their threats they could not be more wrong.

"Countries like Britain and America will not be cowed by barbaric killers."

The western leaders were speaking ahead of a two-day Nato summit in Newport which will begin later today.

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