Stop a rebel leader and others (6)
I believe the answer is:
arrest
'stop' is the definition.
(I know that stop can be written as arrest)
'a rebel leader and others' is the wordplay.
'rebel leader' becomes 'r' (I've seen this in other clues).
'and others' becomes 'rest' (I've seen this in other clues).
'a'+'r'+'rest'='ARREST'
(Other definitions for arrest that I've seen before include "apprehend a law-breaker" , "Stop - detain" , "Take into custody as police do" , "Stop, check (progress)" , "Catch" .)