British singer Leona Lewis was attacked as she signed copies of her autobiography in a central London Bookstore. Police say they arrested a 29-year-old man, who allegedly punched Lewis in the face as she was signing his book. The reason behind this act has not been found so far. The singer was badly shaken up but did not need hospital treatment. Leona Lewis has been nominated for the Grammy Awards thrice; where as she is also the first British singer to gain top position in US charts through her song Bleeding Love.