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police
police officer
police station
self-appointed enforcer (of a rule, standard, etc.); busybody; vigilante; gatekeeper
事故があって、警察が来ました。
There was an accident, so the police came.
事故があって、警察が来ます。
There was an accident, and the police came.
財布を落としたので、警察に届けます。
I dropped my wallet, so I will report it to the police.