Belzer was 78 years old.
Belzer's death was mourned by an original cast member of "Saturday Night Live" and friend Laraine Newman confirming the actor's death on Twitter.
"I'm so sad to hear of Richard Belzer's passing," Newman wrote. I" loved this guy so much.
"He was one of my first friends when I got to New York to do SNL. We used to go out to dinner every week at Sheepshead Bay for lobster. One of the funniest people ever. A master at crowd work."
Belzer was best known for portraying detective John Munch on NBC's "Homicide: Life on the Street" and "Law & Order: SUV" from 1993 to 2016.
A Connecticut native, Belzer was born in Bridgeport, and graduated from Andrew Warde High School (later Fairfield Warde High School) in the town of Fairfield, before attending Dean College in Franklin, Massachusetts.
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