Samuel Koch, 23, suffered serious back and spinal injuries when he failed to fully jump over an approaching car using special spring-powered stilt shoes on the live TV show Wetten, dass…? (Wanna Bet?).
The rest of the show was canceled, as Bieber, 16, wrote on Twitter: "we all don't think it is right to continue. Please pray for Samuel Koch & his family as we wait and hope for his health and safety."
The pop star later added: "Germany I'm sorry we couldn't perform tonight but some things are more important than putting on a show. We will be back I promise. Thank u."
Koch's accident occurred in front of a live studio audience and more than 8 million TV viewers. He underwent surgery Sunday and was put into an artificial coma. His condition was initially life threatening, according to the German newspaper Bild, which quoted a doctor as saying Koch was "in an extremely critical stage."
Wetten, dass…? has been on the air for 29 years. This is the first truly serious accident in its history.