Leona LewisPolice have arrested a man over an alleged assault on singer Leona Lewis at her 'Dream' book signing in London. Lewis' spokesman said the singer had been signing autographs for around 90 minutes when "a guy came up and punched her to the side of the head," BBC reports

The event ended immediately, and Lewis was quickly escorted out and spotted in tears. Lewis' rep said the singer sustained bruising to the side of her head and was left "shaken" by the incident.