Family member mourning at scene of attack in a Saudi mosque on Friday
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Can Saudi coalition defeat Islamic State?

The recent, dramatic gains by Islamic State fighters across Syria and Iraq have prompted fresh doubts over whether the coalition strategy to defeat them is working.

The extremists now control half of Syria, and they have established branches in several Arab countries.

On Friday, its supporters carried out the deadliest terrorist attack in Saudi Arabia in nearly a decade.

Frank Gardner reports.

  • 22 May 2015
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