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AMY WINEHOUSE was released from a London jail Saturday morning, the Associated Press reports. The Grammy winning singer was cautioned by police for common assault, stemming from an incident earlier this week where she allegedly headbutted a fellow bar patron.

The "Rehab" singer was taken into custody Friday afternoon but a doctor decided she was "in no fit state" to be questioned so she was kept in a cell overnight until a doctor gave the go-ahead for her to be interviewed Saturday morning.