The X Factor winner, Leona Lewis, got a shocking moment while she was signing copies of her "Dreams" autobiography at a London bookstore last Wednesday. A guy was punching her on face after Lewis signed his book.

The 24 years old girl had been signing autographs at the bookstore for about 90 minutes. And then this guy came up and punched her to the side of the head. Lewis was looking shocked and terribly shaken, though she did not have to go to hospital due to her injury.

According to an eyewitness at the store, this attacker guy walked up to her with the book, Lewis signed it and, as she looked up to him, he just punched her. Lewis running out with her hand over her eye and left this guy get caught by her security crew.

Although Lewis did not need to go to the hospital, she did cancelled her appearance on BBC's The One Show that night. Wow, who knows a signing show could be so dangerous for celebrity.

Lewis will release her new album "Echo" on November 17, and she has already put out a new single called "Happy".