Ozzy Osbourne cancels show over "vocal concerns"

(CBS News) Ozzy Osbourne cancelled a concert in Germany on Wednesday because of "vocal concerns," reports say.

A source told TMZ the heavy metal singer was supposed to take the stage after Black Label Society finished their set, but instead fans were greeted by another man who announced that Osbourne was unable to perform due to a medical condition.

A rep for the Black Sabbath frontman insisted that he is in good health, but cancelled due to "vocal concerns," reports E! News.

Osbourne's cancellation comes less than a week after his son, Jack, announced that he was diagnosed with multiple sclerosis.