informer
noun /ɪnˈfɔːmə(r)/
/ɪnˈfɔːrmər/
- a person who gives information to the police or other authority
- The bomber turned (= became) police informer to escape prison.
- One of the gang members had turned informer.
Oxford Collocations Dictionaryadjective- police
- become
- turn
- a network of informers