Criminal worker found after awful crimes (9)
I believe the answer is:
miscreant
'criminal' is the definition.
(I've seen this before)
'worker found after awful crimes' is the wordplay.
'worker' becomes 'ant' (worker is a type of ant).
'found after' means one lot of letters go next to another.
'awful' indicates an anagram.
'crimes' anagrammed gives 'miscre'.
'ant' put after 'miscre' is 'MISCREANT'.
(Other definitions for miscreant that I've seen before include "Offender" , "Villainous" , "scoundrel" , "Wretch" , "criminal" .)