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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Showers becoming confined to the west overnight, some sunshine Tuesday.
Windy but drier overnight. Chilly with a few showers Tuesday.
Private Cheryl James, 18, was discovered with a fatal bullet wound. Lawyers suggest possible "third party involvement" in her death.