[naturally2014]

I'd guess a third option, actually: It's just a best guess, but they don't like being questioned.

If they had damning evidence it'd be in their interest to release it.

[walshemj]

Not if it would give any humint sources away and they may have kicked out people to allow a source to step into their shoes - as the UK did to put there man in as the Resident in London

[porpoisemonkey]

It's somewhat obvious from the context but for anyone not familiar with military jargon I think the parent post meant to say "humint" instead of "humit" which is short hand for "human intelligence" or in layman's terms "spies".

[walshemj]

oops my bad