Warner Bros studio said on Wednesday it was working to remove a 36-minute Internet leak of the new 'Harry Potter' film ahead of what industry experts said could be the biggest opening weekend box office yet for the major movie franchise.

Industry watchers and even the movie's parent studio, Warner Bros, think the film could eclipse the $100 million mark in the US and Canada over its first three days in theatres, starting on November 19. They are even predicting a full run of more than $1 billion in global ticket sales.

Those eye-popping numbers were being talked about even as 36 minutes of 'Harry Potter and the Deathly Hallows: Part 1' turned up on a file-sharing website Tuesday night ahead of the movie's premiere in numerous countries around the globe.

Warner Bros said in a statement that the excerpt was 'stolen and illegally posted on the Internet. This constitutes a serious breach of copyright violation and theft of Warner Bros property.

'We are working actively to restrict and/or remove copies that may be available. Also, we are vigorously investigating this matter and will prosecute those involved to the full extent of the law,' said the Time Warner studio.

The first six 'Harry Potter' movies, which are based on the best-selling books about a British boy wizard by author JK Rowling, have earned $5.42 billion at world-wide box offices, according to California-based BoxOfficeMojo.com.

Dan Fellman, Warner Bros domestic distribution chief, said the film should top $100 million in the US and Canada during its first weekend in theatres. Throughout the movie's entire life in theatres around the globe, he sees ticket sales rising to the rare level of more than $1 billion.

'This one is heading north of $100 million,' Fellman told Reuters. And when asked about it's ability to be the first 'Harry Potter' movie to pass the magic $1 billion mark worldwide, he replied, 'I definitely think it will.' Fellman was not alone.

'This is going to be the biggest opening yet. It could surpass the $102.7 million US opening for 'Goblet of Fire' in 2005',' said Paul Dergarabedian, box office tracker at Hollywood.com.

'This movie is the beginning of the end of the Harry Potter phenomenon and the culmination of a decade. It is hard not to put too high a figure on it,' Degarabedian told Reuters.

The seventh and penultimate movie about the adventures Harry and his Hogwarts School friends will get its largest ever opening on Imax screens. Imax said 'Deathly Hallows' would open on 239 of its screens in North America, and 117 screens internationally.
The final book in the series is split into two films. The film franchise ends its run in July 2011 with 'Deathly Hallows: Part Two,' which will be in 3D.-Reuters