Free falling songstress and exotic substance enthusiast Amy Winehouse (pictured left in happier times) is being investigated by the police for allegedly slugging a fan in the face when she troubled the performer for a photograph. A source says Winehouse tossed the jagged cluster of bones that forms her fist into fan Sherene Flash's eye after she asked Winehouse to pose for a snapshot with her following this week's End of Summer Ball. Which is especially sad, since Winehouse started the summer by getting caught on video decking a fan and falling down.

"Sherene asked Amy if she could take a photo," the source alleged. "Amy was OK at first, but then Sherene asked if a friend could get in the shot, Amy lashed out." The source said the 25-year-old, who has had a number of medical and substance-related problems in the past year, had just completed a "tragic" on-stage performance with her goddaughter Dionne Bromfield. "It was tragic—she seemed totally wasted," the source told the Mail regarding Winehouse's performance Thursday. "She was jumping all over Dionne as the poor girl tried to sing for the crowd. Amy didn't really sing a single note—it sounded more like she was grunting down the mic."