[Corrected 3:20 p.m.] An earlier post said he died Tuesday.
The cause and place of death were not immediately known.
McDuffie, a Detroit native, wrote comics for the New York-based DC and Marvel, including runs on "Batman: Legends of the Dark Knight," the Fantastic Four and the Justice League of America. He also penned several animated features, including the just-released "All-Star Superman," ''Justice League: Crisis on Two Earths" and the animated TV series "Static Shock" and "Ben 10: Alien Force."
He founded publishing company Milestone Media in 1992.
[updated 5:55 p.m.] More from the Associated Press:
News of McDuffie's death was first reported Tuesday by the website Comic Book Resources. As recently as last week, McDuffie attended the premieres of the new "All Star Superman" film in Los Angeles and New York, and was scheduled to appear at an event this week at Golden Apple Comics in Los Angeles.
McDuffie tweeted last week that he was "Taking a break from a script I owe to attend the LA premiere of ‘All Star Superman.’"
McDuffie's work for Marvel included "Damage Control," which took a serious but fictional look at a company whose job it was to clean up the damage — both physical and legal — resulting from battles between superheroes and supervillains. In 1992, however, he formed the comic book company Milestone Media, which gave him the freedom and leeway to create his own characters, many of whom were of differing ethnic backgrounds.
Milestone Media focused on multicultural superheroes including "Hardware," "Icon," "Blood Syndicate," "Xombi" and "Static," which was turned into the popular children's cartoon "Static Shock," on which he served as a story editor.
McDuffie also wrote for other titles and characters, too, including Black Panther and Deathlok.
Besides comics, McDuffie was a producer and story editor on Cartoon Network's "Justice League Unlimited," and wrote and produced episodes of other cartoons, including "What's New, Scooby Doo?," "Ben 10: Ultimate Alien" and "Teen Titans."
McDuffie was nominated for two Emmy Awards for "Static Shock," a Writers Guild award for "Justice League" and three Eisner awards for his work in comic books, his website said.
McDuffie's death took his colleagues and friends by surprise.
Dan DiDio, co-publisher of DC Entertainment, said the writer "left a lasting legacy on the world of comics that many writers can only aspire to. He will not only be remembered as an extremely gifted writer whose scripts have been realized as comics books, in television shows and on the silver screen, but as the creator or co-create of so many of the much-loved Milestone characters, including Static Shock."
Added DiDio: "The industry has lost a true talent."
Tom Brevoort, Marvel's senior vice president for publishing, said McDuffie was a force behind bringing more diversity into comics.
"He was very interested in creating a wider range of multiculturalism in comics, having been profoundly affected by the example of the Black Panther when he was growing up, and wanting to give that same opportunity to others of all races, creeds and religions, which is one of the reasons he left Marvel and co-founded Milestone," Brevoort told the Associated Press. "And he eventually came back to write both 'Beyond!' and 'Fantastic Four' for me."
— Associated Press