Jay-Z

U2 and Jay-Z

Shakira

Leona Lewis

Green Day

Katy Perry

Tokio Hotel

Foo Fighters

(from left) Leona Lewis, Clive Davis and Carrie Underwood attended a Grammy party in 2008 (AP Photo by Chris Pizzello)

The cover to Leona Lewis' autobiography. The book will be in stores Thursday (Oct. 15).

Pop singer Leona Lewis was hit in the head Wednesday (Oct. 14) while she was signing autographs for fans. 

The 24-year-old was hit by a man at a bookstore while she was promoting the release of her autobiography. 

Her publicist issued a statement on Facebook that said “Leona was the victim of an unprovoked attack this afternoon at her book signing. The police were called immediately and medical attention has been sought. Leona is understandably shaken and apologises to the fans she was unable to meet and complete signings.”

According to the Associated Press, a 29-year-old man was taken into police custody, and his motive is unknown. 

Lewis became famous in 2006 when she won the U.K. talent show “X Factor,” which is similar to “American Idol.”

Her hit songs include “Bleeding Love,” ‘I Will Be” and “Better In Time.” Her autobiography titled Dreams will be in stores Thursday (Oct. 15).

The show featured appearances by Jennifer Hudson, Kelly Clarkson, Miley Cyrus, Leona Lewis, Melissa Etheridge, Jordin Sparks, Sheryl Crow, Martina McBride, Adele, India Arie, Kathy Griffin Liza Mineli, and Stevie Wonder. (Stevie was the only male. He was the honorary diva).

Video clips of some of the performances are posted below.

Jennifer Hudson

Kelly Clarkson

Martina McBride and Jordin Sparks

Stevie Wonder and Jennifer Hudson

Melissa Etheridge and Kelly Clarkson

Paula Abdul and Kathy Griffin

Paula Abdul and Liza Mineli