flying squad 
noun British
A division of a police force or other organization which is capable of reaching an incident quickly: the gang were caught by the Flying Squad a medical flying squad...
- The ultras suddenly surfaced at Lak Chowk and opened fire from close range on the flying squad of the Maisuma police station.
- I think the French police have a culinary flying squad that swoop on amateur cooks and destroy cheap and nasty ingredients.
- The flying squad section of Scotland Yard, annoyed at recent cut backs to the police budget have decided to take matters into their own hands.