The deluge on Monday - which appeared to take the authorities by surprise - saw people sleep in their cars or abandon them as motorways and A roads clogged up.

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"The number of sites of disorder was something we hadn't experienced in the city before - and that did take us by surprise, " he said.

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The French right-of-centre newspaper Le Figaro reports that Mr Hollande's announcement on the TF1 channel appeared to take party colleagues by surprise.

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