Irish rockers U2 cut short a performance in Germany as lead singer Bono bizarrely suffered a "complete loss of voice".

It's still unknown the mysterious reason for Bono's sudden vocal chord issue.

“We don’t know what has happened and we’re taking medical advice,” said a statement signed by band members Adam Clayton, Larry Mullen, and The Edge.

“We’re so sorry for tonight’s cancellation. Bono was in great form and great voice prior to the show and we were all looking forward to the second night in Berlin, but after a few songs, he suffered a complete loss of voice,” the statement added.

“As always, we appreciate our audience’s understanding and all our fans’ support in Berlin and those who traveled from afar. We will update you very soon," it concluded.

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The four-piece band had performed a stellar full set the night previous.

U2 fan site Atu2 stated that Bono attempted to sing hit song "Beautiful Day" before being forced to leave the stage. Moments earlier, he had visibly struggled to serenade the audience with "Red Flag Day". 

The Irish Independent notes that at this moment, he told the crowd he couldn't continue before rushing off-stage.

According to the New York Times, Bono told had the crowd moments earlier, “I’ve lost my voice and I don’t know what to do..I was singing like a bird 10 minutes ago. I’m sure it will pass.”

It appears that the 58-year-old has never had to halt a performance before due to vocal issues. 

Actress Ashley Judd, who happened to be at the show, posted footage of Bono’s performance on Twitter, commending the singer and reminding everyone that he's not invincible.

The band are due to perform next on September 10th.

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