Justice League star Ray Fisher has alleged Joss Whedon was "abusive" and "gross" on the set of the movie.
The 32-year-old actor played Victor Stone and his alter-ego Cyborg in the 2017 movie, and has now claimed Joss - who was brought in as the director to replace Zack Snyder after a family tragedy forced him to drop out - was "unprofessional" while on set, and called his behaviour "completely unacceptable".
Ray tweeted: "Joss Whedon's on-set treatment of the cast and crew of Justice League was gross, abusive, unprofessional, and completely unacceptable.
"He was enabled, in many ways, by Geoff Johns and Jon Berg. Accountability>Entertainment. (sic)"https://twitter.com/ray8fisher/status/1278362556214755329
Joss, 56, was hired to oversee the reshoots of the movie and finish the post-production work, and was responsible for injecting a lighter tone and more jokes into the Justice League theatrical cut, which prompted fan demand for Zack Snyder's original vision to be honoured.
Ray's tweet comes just days after he previously slammed Joss on social media, when he shared a clip from Comic Con 2017 which saw Ray speak highly of the director, calling him a "great guy".
The actor wrote alongside the clip: "I'd like to take a moment to forcefully retract every bit of this statement."
Meanwhile, it was previously claimed Zack Snyder would be bringing his version of Justice League - which is thought to be a darker take on the story - to HBO Max next year, either as a lengthy new film or a six-part series.
He explained: "It will be an entirely new thing, and, especially talking to those who have seen the released movie, a new experience apart from that movie."