The two men were shot by two men wearing Afghan police uniforms.
The inquest heard an intelligence report that said "insider threat" was difficult to detect. Insurgents and the Taliban used this kind of attack as a tactic and there had been no increase in this kind of threat.
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Journalist Steve Hewlett, who shared his experience of battling cancer on BBC Radio 4, has died of the disease at the age of 58.
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Adam Colclough from the Green Party answers five questions ahead of the Stoke Central by-election.