Watchmen creator Alan Moore calls Frank Miller's Sin City "unreconstructed misogyny" and 300 "homophobic and completely misguided".
Moore's outburst was in response to comments made by the American Miller on the Occupy movement via his blog last month, where he described it as "nothing but a pack of louts, thieves, and rapists, an unruly mob, fed by Woodstock-era nostalgia and putrid false righteousness".
In an extended tirade, Miller added: "These clowns can do nothing but harm America. Wake up, pond scum."
While admitting that he and Miller "have diametrically opposing views upon all sorts of things" in an interview with British independent publisher Honest Publishing, Moore appears to have taken particular umbrage at the Occupy comments.
He described the anti-capitalist protests as "a completely justified howl of moral outrage", adding that they had been "handled in a very intelligent, nonviolent way".
Moore went on: "If it had been a bunch of young, sociopathic vigilantes with Batman makeup on their faces, [Miller would] be more in favour of it."
He then unleashed a torrent of abuse aimed at Miller's work:
"Frank Miller is someone whose work I've barely looked at for the past 20 years. I thought the Sin City stuff was unreconstructed misogyny; 300 [a 1998 comic book series] appeared to be wildly ahistoric, homophobic and just completely misguided. There has been a rather unpleasant sensibility apparent in Frank Miller's work for quite a long time."
Both authors have been hugely influential in the comic book industry. Moore's Watchmen and V for Vendetta have been turned into successful feature films, while Christopher Nolan's forthcoming film The Dark Night Rises is said to be loosely based on Miller's Batman: The Dark Night Returns series.