Social networking site Facebook is under threat of being closed. The founder of rival site, ConnectU, have filed a lawsuit saying that Facebook founder Mark Zuckerberg stole their idea when they were students at Harvard. 

The lawsuit accuses the 23-year-old entrepreneur of copyright infringement, fraud and stealing trade secrets.
Cameron Winklevoss, Tyler Winklevoss and Divya Narendra, the founders of ConnectU, say they asked Zuckerberg to help them program their site in 2003, but he stalled deevlopment and then launched Facebook which, they claim, stole their idea, code and business plan.
ConnectU filed a similar case against Zuckerberg in 2004, but it was dismissed on a technicality.
Meanwhile, Facebook has launched a defamation counter-suit.
Facebook boasts 31-million users worldwide and could be worth as much as $10-billion.