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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After a wet and windy start, rain will clear to the north to leave it dry, with easing winds but largely cloudy skies.
Early rain will clear northwards during the morning, allowing drier conditions behind.
Thousands of patients have had their operations and appointments cancelled despite a strike by junior doctors being called off.