X-Men pic "Wolverine" leaks online

Hugh Jackman waves to the media in German cinemas on December 25.

LOS ANGELES (Hollywood Reporter) - "X-Men Origins: Wolverine" made an unauthorized debut online Tuesday, even though the film isn't set for U.S. release until May 1.

Web sites described the illegal download as a nearly complete, high-quality copy, but 20th Century Fox, the studio behind the film, said Wednesday that it included temporary sound and music and was missing effects and some scenes, with other scenes unedited.

The studio issued a statement saying, "We immediately contacted the appropriate authorities and had it removed," though once a film begins circulating online, it can be difficult to stamp it out.

Because of forensic marks, the studio said it would be able to determine the source of the leak, though it did not immediately disclose it, saying: "The FBI and the MPAA (Motion Picture Association of America) also are actively investigating this crime. We are encouraged by the support of fansites condemning this illegal posting."

"Wolverine," a spinoff of the Fox/Marvel "X-Men" franchise, stars Hugh Jackman and is directed by Gavin Hood. Its international rollout kicks off April 28, and it will have opened in most territories worldwide by May 1.