Leona Lewis is scared to go out in crowded places since she was attacked at a book signing.

The 27-year-old singer was punched in the face by a man masquerading as a fan in 2009 as she autographed copies of her autobiography 'Dreams' at a London book shop.

Although she only received minor bruising in the attack, Leona admits the incident has had a long-term effect on her psychologically and far more wary of her fans and especially ''dodgy'' looking men.

Speaking as she signed copies of her new album 'Glassheart' at HMV on London's Oxford Street on Monday (15.10.12), she said: ''I'm definitely more aware when I go out in public and it has 100 per cent had an effect on me and my life.

''But I've just got to deal with it. I don't like going out where it's really, really crowded. I'm obviously very suspicious of any men who look a bit dodgy.''

The 2009 attack shook her up so much that she had avoided doing anymore fan signings until now.

Leona had a large security team with her on Monday to protect her, and the 'Trouble' hitmaker admitted the meet and greet with fans brought back memories of the assault.

She told The Sun newspaper: ''I don't feel like anything is going to happen to me but being in that situation brings back memories.''