Source of stings (3)

I believe the answer is:

fbi

(Other definitions for fbi that I've seen before include "law enforcers" , "Initially, J Edgar Hoover's law force" , "US law enforcement agency" , "J. Edgar Hoover long its director" , "J. Edgar Hoover's organisation" .)

I've seen this clue in the Newsday.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.