They were accused of 'spying' for a foreign government.
a 'spy' camera/plane [=a camera/plane used for spying]
a 'spy' novel/thriller [=a novel/thriller about spies]
(..) You've taken an interest in Sansa Stark. Have I? Because I spoke to her once in this garden and one of your little spies came running to tell you? Why shouldn't I take an interest? - She's an interesting girl. - Is she? (..)2013 TvShow: Game of Thrones Title: And Now His Watch Is Ended Season: 3 Episode 4
(..) of your little birds might have knowledge of my sister's intentions to-- End your life? I didn't inherit Littlefinger's spies along with his position, I'm afraid. Which is why I'm coming to you. - I need proof. - Proof? (..)2013 TvShow: Game of Thrones Title: And Now His Watch Is Ended Season: 3 Episode 4