Chinese cinemas cancelled all screenings of Quentin Tarantino's "Django Unchained" just as it was released on Thursday, local media said, with one viewer adding a showing was stopped after one minute.
China strictly censors films and other media for sexual and political sensitivities, and limits distribution of foreign films to protect the domestic industry.
"'Django Unchained', because of technical reasons, has been stopped from being shown nationwide for the time being," the popular web portal Sina reported, citing a notice distributed to cinema companies.
It quoted unnamed industry insiders as saying that nudity prompted the sudden censorship and said it was not clear when the film would return to screens.
The film starring Jamie Foxx, Christoph Waltz and Leonardo DiCaprio tells the story of a freed American slave who, supported by a bounty hunter, seeks to rescue his wife from a plantation owner.
A user of China's Twitter-like Sina Weibo microblog service said he had been watching the film when "after just one minute it stopped!"
Other posters guessed that nude scenes forced the interruption, while another cited the "dangerous" theme of underdogs rising up by force.
The main character "was continually repressed and enslaved by the slaveowner, then suddenly got his hands on a gun and rebelled in the name of love and freedom", the user said.
The censors' "cutting hands are fiercer than that of a slaveowner, insistent on making Django a eunuch", wrote another.
A blurred photo showing the main character, played by Foxx, hanging naked upside down, which had accompanied online reports on the cancellation, appeared to have been removed by Thursday afternoon.
"Django Unchained" won Academy Awards this year for best supporting actor and best screenplay, and was Tarantino's first film to secure a commercial release in China according to the Hollywood Reporter.
The director's trademark graphic violence survived the official pre-release censorship, with only minor tweaks such as the blood being coloured darker and its spatter slightly lessened, Sony Columbia executive Zhang Miao told the Southern Metropolis Daily.
The General Administration of Press and Publication, Radio, Film and Television, China's central censorship body, could not be reached for comment.
The rules governing censorship are opaque and reasons are not provided for why cuts are made, but negative portrayals of contemporary politics are often banned, as are issues that it believes could lead to social unrest.
Nonetheless, thanks to rampant piracy in China, fans have already been able to watch the original version of "Django Unchained" on DVD or online -- even before the movie hit theatres.
Earlier this year censors cut out 40 minutes of love scenes and other parts of the Hollywood film Cloud Atlas, triggering complaints that it made an already complicated plot more confusing.
Scenes were also removed from the latest James Bond film "Skyfall", including a shooting in Shanghai, along with mentions of prostitution in Macau, a special administrative region of China, and torture by Chinese security agents.
China limits foreign film releases to 34 a year, but despite competing against 893 locally made movies last year they generated 51 percent of the market's 17 billion yuan ($2.7 billion) revenue -- the second largest in the world.