Disney confirmed the Deadline report, but had no further comment.
Gunn had already written a script for the third “Guardians,” though production on the film will likely have to wait until “Suicide Squad” is completed.
The first two “Guardians of the Galaxy” movies became a surprise hit for Marvel and Disney, totaling $1.6 billion in international box office. The characters have been featured in the latest “Avengers” storyline, beginning with “Infinity War” and continuing with the upcoming “Endgame.” A Guardians of the Galaxy attraction has also opened at Disneyland.
The offensive tweets were primarily posted between 2008 and 2012. When he was fired, Gunn explained that earlier in his career he had “viewed myself as a provocateur, making movies and telling jokes that were outrageous and taboo. As I have discussed publicly many times, as I’ve developed as a person, so has my work and my humor.”
CNN’s Frank Pallotta contributed to this story.