Acted like a vandal and was dismissed (6)
I believe the answer is:
sacked
'dismissed' is the definition.
('sack' can be a synonym of 'dismiss')
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for sacked that I've seen before include "Dismissed from employment" , "Fired" , "Dismissed or pillaged" , "Given one's P45" , "Informally dismissed from job" .)