The actor, who memorably played shotgun-wielding stick-up man Omar Little on HBO’s acclaimed crime drama, was found dead at his home in Brooklyn on Monday, police in New York said.
No cause of death was given.
A representative confirmed the news, describing his death as an “insurmountable loss”.
Tributes have flooded in for the star, who as well as his role on The Wire earned fame and plaudits for playing Albert “Chalky” White on the HBO series Boardwalk Empire.
Oscar-winning filmmaker Spike Lee, who also grew up in Brooklyn, shared a picture of himself and “my brother” together.
He wrote on Instagram: “Our Brother Passed Away Today In His Home, Da People’s Republic Of Brooklyn. I’m Shook. Drinking A Bottle Of Italian Red Wine-Brunello Di Montalcino By Myself. Our Greats Are Leaving Us Left And Right. GOD BLESS.”
Wendell Pierce, who starred alongside Michael on The Wire, playing Detective Bunk Moreland, also paid tribute.
He wrote a moving Twitter thread and said: “The depth of my love for this brother, can only be matched by the depth of my pain learning of his loss.
“A immensely talented man with the ability to give voice to the human condition portraying the lives of those whose humanity is seldom elevated until he sings their truth.”
David Simon, creator of The Wire, also paid tribute.
He posted a picture of the actor to Twitter and wrote: “Too gutted right now to say all that ought to be said.
“Michael was a fine man and a rare talent and on our journey together he always deserved the best words. And today those words won’t come.”
Isiah Whitlock Jr also starred alongside Michael in The Wire and paid tribute on Twitter.
He said: “Shocked and saddened by the death of Michael K Williams. One of the nicest brothers on the planet with the biggest heart. An amazing actor and soul. May you RIP. God bless.”
Chart-topping singer Mariah Carey shared smiling pictures of her and Williams together.
She wrote: “A beautiful soul, a beautiful person, I’ll miss you always. Thank you for blessing us with your talent.”
Award-winning actress Kerry Washington said: “So heartbroken. @bkbmg thank you for the beauty and joy you brought to the world.
“Sending love and prayers to your friends, family and everyone who adored you me included We adore you Sir.”
Oscar-winner Viola Davis said: “No! So sad. Man do I wish this were a different ending. Rest well.”
Other stars from the entertainment world have also paid tribute across social media…
In its statement, HBO, the network where Michael became a star, described his death as an “immeasurable loss”.
It said: “We are devastated to learn of the passing of Michael Kenneth Williams, a member of the HBO family for more than 20 years.
“While the world is aware of his immense talents as an artist, we knew Michael as a dear friend who was beloved by all who had the privilege to work with him.
“We send our deepest condolences to his family for this immeasurable loss.”
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