Sounds like he OD'd
which is somewhat ironic given his association with "The Wire". Pretty ####ing sad- he was definitely one of the best characters on that show, despite stiff competition. He was also really good on "Boardwalk Empire" and generally effective in the (mostly small, probably because of that scar) film roles he landed over the years.
TIL that Williams plays Bob Dylan in this: https://en.wikipedia.org/wiki/Beastie_Boys_Story
. Anyone seen it?