Ran away from rifle fire (4)
I believe the answer is:
sack
'fire' is the definition.
(dismiss someone from their job)
'ran away from rifle' is the wordplay.
'ran away' becomes 'ran' ('run' can be a synonym of 'run away').
'from' suggests deleting specific letters.
'rifle' becomes 'ransack' (both can mean to search for and steal).
'ransack' with 'ran' removed is 'SACK'.
(Other definitions for sack that I've seen before include "Fire the old drink?" , "Dismissal - sherry!" , "present holder" , "Large hessian bag" , "Fire - plunder and destroy" .)