MI6 chief Sir John Sawers said the leaks from NSA whistleblower Edward Snowden "have been damaging and put operations at risk."
Al-Qaeda is "lapping up" the leaks and Britain's enemies are rubbing their hands with glee, the British intelligence chief added.
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The First Lady's masterly performance, combined with Bernie Sanders' impressive speech, saved a convention that was fraying at the edges.
The High Court will hear a legal challenge to Labour's decision to guarantee Jeremy Corbyn a place on the party's leadership ballot.
Russian Foreign Minister Sergei Lavrov brushed aside accusations that Moscow was behind the hacking of internal Democratic Party memos.