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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US 'will not be intimidated' in fight against IS

The United States "will not be intimidated" in the fight against Islamic State, President Obama said.

Speaking after the murder of second US journalist Steven Sotloff, President Obama said: "Americans are repulsed by their barbarism. We will not be intimidated".

"Their horrific acts only unite us as a country and stiffen the resolve against these terrorists," President Obama said.

The President said it will "take time" to defeat militants, warning Islamic State posed a very serious threat not just to Iraq but entire region.

However, Mr Obama vowed to target "those who make the mistake of harming Americans".

"Our reach is long and justice will be served," he said.

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