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.
'leader' says to take the initial letters.
'and others' becomes 'rest' (I've seen this in other clues).
The first letter of 'rebel' is 'r'.
'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" .)