Actor Michael K. Williams, best known for playing Omar Little on The Wire, has died aged 54.

Williams created one of the most popular characters on US television in recent decades as Little, breaking TV ground as an openly gay man whose sexuality wasn’t central to his role.

Williams was found dead on Monday afternoon in his Brooklyn penthouse apartment, New York City police said.

His death was being investigated as a possible drug overdose.

Little, a “stick-up boy” based on real figures from Baltimore, was probably the most beloved character among the devoted fans of The Wire, the HBO show that ran from 2002 to 2008 and is re-watched constantly in streaming.

The Brooklyn-born Williams was also a ubiquitous character actor in other shows and films for more than two decades, including roles on the HBO series Boardwalk Empire and Lovecraft Country, and in the films 12 Years a Slave, Community and Assassin’s Creed.

As Little, he played a criminal with a strict moral code, known for taking advantage of a reputation for brutality that wasn’t always real.

And he spoke many of the show’s most memorable lines, including, “A man gotta have a code” and “All in the game yo, all in the game.”

Co-stars and fans mourn ‘wonderful man’

Devastated fans and friends of Williams have written heartfelt tributes online to his work and good character.

Joel McHale, who appeared on sitcom Community alongside Williams tweeted that he was “such a good, kind wonderful man … an actor for the ages.”

Tweet from @joelmchale

Lord of The Rings actor Elijah Wood paid tribute to both Williams and to the passing of French actor Jean-Paul Belmondo, known best for his role in Breathless, who both passed on the same day.

Tweet from @elijahwood

Williams’ fans took to social media to celebrate his talent, sharing their favourite moments from his catalogue, particularly from his role in The Wire.

Tweet from @RichardOcelot

IMDB also posted a a tribute on Twitter to the actor’s “life and career”.

“We pay tribute to the life and career of Michael K. Williams, the Emmy-nominated actor best known for The Wire, Boardwalk Empire, and Lovecraft Country,” IMDB wrote.

Williams appeared in all five seasons of The Wire from 2002 to 2008, his character growing in prominence with each season.

-with AAP