Wanton destroyer (6)
I believe the answer is:
vandal
'wanton destroyer' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for vandal that I've seen before include "Ger. tribesman; one who damages property" , "Lout causing damage to property" , "Destructive person" , "Person causing destruction to property" , "One who wilfully defaces or destroys property" .)