Horror film Texas Chainsaw 3D has unexpectedly topped the U.S. box office, ending The Hobbit's three-week reign, BBC News reported.

The movie, set immediately after the events in Tobe Hooper's classic 1974 slasher picture, made $23m (£14.3m) in its opening weekend.

It immediately made back its $20m budget for film company Lionsgate.

Quentin Tarantino's Django Unchained held firm at number two, making $20.1m, while The Hobbit: An Unexpected Journey slipped to number three.

Peter Jackson's return to Middle Earth has so far taken $263.8m (£164m) in the U.S., and about $825m (£514m) globally.

Fourth place went to musical adaptation Les Miserables, starring Hugh Jackman and Anne Hathaway. It has now passed the $100m mark, the first musical movie to do so in under 14 days.

And fifth position went to Billy Crystal's big screen comeback Parental Guidance, about an elderly couple left in charge of their grandchildren.