Sum 41 have cancelled their appearance on the 'Vans Warped Tour' this week following Deryck Whibley's injury.

The singer was attacked in a bar in Japan last week, leading him to slip a disc in his back, so his bandmates have decided to pull out of the remaining five shows scheduled as part of the tour.

A statement said: "Knowing that they are unable to deliver their signature high energy show, Sum 41 made the tough decision that a break is needed while Deryck begins rehabilitation for the slipped disc."

While the band - who have previously played more than 20 'Warp Tour' dates this summer across the United States and Canada - are disappointed to let down their fans, they know Deryck's health comes first.

Drummer Steve Jocz said: "We are very disappointed that we have to pull off the tour. But we know that it would be more frustrating for the fans if we can't give it our all. Deryck is doing everything he can to get himself better and we're there for him."

The group hope to be back on the road again in Europe at the end of the month.

The assault on Deryck is still under investigation in Japan.