A poster of the film 'Fury'. The most popular title leaked online has been the studio's World War 2 film, "Fury." [Photo/Agencies]

Sony has been the target of another massive cyber attack, with this latest assault resulting in at least five of the company's newly released and upcoming movie titles being pirated online.

Among the films known to have been leaked so far is Sony's big-screen remake of the classic musical "Annie," which opens in three weeks stateside. But the most popular title leaked online has been the studio's World War 2 film, "Fury."

The film, which hit theaters in China on November 21st, has been illegally downloaded more than one-million times since its DVD screener was leaked last Monday, according to data from web-piracy tracking site, Excipio.

Last week, an image of a skeleton appeared on Sony computers with a message that read "Hacked by #GOP," with the group calling themselves "Guardians of Peace" claiming responsibility.

The message threatened to reveal Sony's "secrets and top secrets" if certain demands were not met.

Sony says it's working closely with law enforemcent to address the issue, giving no further details on the investigation.

Sony was the target of another attack in July, which led to the film "Expendables 3" being leaked online three weeks before the movie's release date.

Two men in London were arrested last week in connection to that attack.

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