(CNN)The most deadly Islamist terrorist attack ever in France followed weeks of warnings from French officials that the threat had risen to unprecedented levels. Late last year French Prime Minister Manuel Valls said his country had never faced a greater terrorist threat. Officials tell CNN the threat of terrorist attack in the European Union is greater than at any time since 9/11 because of the emergence of jihadist safe havens in Syria and Iraq. But no country faces a greater terrorist threat than France, with support for ISIS running deep among disenfranchised immigrant communities in the rundown, crime-ridden banlieues that surround many French cities.
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Most deadly Islamist terrorist attack ever in France followed weeks of warnings from French officials
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The threat of a terrorist attack in the EU is greater than at any time since 9/11, officials say
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Support for ISIS runs deep among disenfranchised immigrant communities
No evidence has been publicly released suggesting @placeholder leadership signed off on the plots.