British singer Leona Lewis arrives at the Recording Academy's Clive Davis pre-Grammy party in Beverly Hills, California February 7, 2009. REUTERS/Danny Moloshok

Leona Lewis ran out from a book signing in London on Wednesday after being attacked by an anonymous man, according to reports.

Her boyfriend Lou Al-Chamaa was with her at the signing, the Guardian newspaper reported.

Lewis was promoting her autobiography Dreams at the event when a man approached her with one book, she signed it, and as she looked up he punched her in the face, a witness told the BBC.

The diva reportedly ran out of the place with a hand on her eye.

Suddenly the security all jumped on him [the man] and they were trying to pull him out and he was just laughing, he thought it was funny, an eyewitness said, according to the British network.

The man was arrested over the incident.

Leona's understandably badly shaken and apologizes to the fans she was unable to meet and complete signings for, the singer's spokesman said, BBC noted. She sought medical attention but was unharmed.