Bono Bono

U2 lead singer Bono underwent emergency back surgery in Germany on Friday, according to the band's website.

Bono (real name: Paul Hewson) sustained an injury while preparing for the next leg of U2's 360-Degree tour. The 50-year-old Grammy winner is expected to remain hospitalized for the new few days.

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Because of the operation, U2 has postponed their June 3 concert in Salt Lake City, Utah. It's unknown whether more dates will be canceled.

"We hope to get things resolved as soon as possible," said Paul McGuinness, U2 band manager.