In armed attacks, coppers can be shot! (6)
I believe the answer is:
rapids
'in armed attacks coppers can be shot' is the definition.
I can't tell whether this definition defines the answer.
'in armed attacks coppers' is the wordplay.
'in' indicates putting letters inside.
'armed attacks' becomes 'raids' (raiding is a kind of attacking. I am not sure about the 'armed' bit.).
'coppers' becomes 'p'.
'raids' enclosing 'p' is 'RAPIDS'.
Can you help me to learn more?
(Other definitions for rapids that I've seen before include "Current hazard" , "Part of a river where the current is very fast" , "Fast-flowing and turbulent part of a river" , "Fast-flowing stretch of river, white water" , "White water area" .)