On arrival at mission, all of our staff are fully briefed on the situation and the measures in place. That includes not just the physical security measures that they're aware of—gates and access—but also the operational security, which can supplement and in some cases compensate for physical security that needs to be enhanced. That includes movement protocols, go/no-go areas in their mission locale, the type of escorts, the local guard service required for moving outside the mission environment, radio protocols, communications check-ins, all of these types of things.
On February 26th, 2019. See this statement in context.