Cockney Chuck's suddenly stopped (5)
I believe the answer is:
froze
'suddenly stopped' is the definition.
(I've seen this before)
I cannot understand how the remainder of the clue works.
(Other definitions for froze that I've seen before include "stopped moving altogether" , "Suddenly stood motionless" , "E.g. turned to ice" , "Didn't move" , "Became motionless" .)