Violent criminal (7)

<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">violent criminal</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for ruffian that I've seen before include "Hoodlum" , "Violent, lawless person" , "Hooligan" , "Funfair (anag)" , "Thug" .)
(Other definitions for hoodlum that I've seen before include "Aggressive young criminal" , "Person vandalising" , "Small-time criminal" , "Young thug or criminal" , "American thug" .)
(Other definitions for gangster that I've seen before include "Villain" , "Mobster" , "Typical Cagney role" , "Member of a mob like Al Capone" , "Hoodlum" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">violent criminal</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for thug that I've seen before include "16 21 [INDIAN IMPORT]" , "A vicious or brutal ruffian" , "Violent hoodlum" , "Violent lout" , "Rough" .)