"The organiser of Rock am Ring, working closely with the security authorities, have ended ahead of schedule the festival today," the police said. "The background to this was a concrete warning that made it impossible to rule out a terror threat."

"We cannot provide any further details on the background information," the statement added.

Thousands of festival-goers sang You'll Never Walk Alone as they left the arena.

More than 80,000 music fans had travelled to the Nuernburgring for the festival.

The German band Rammstein was the headline act last night, but had not yet started playing.

The suicide bombing at a pop concert in Manchester on May 26 led to changes in the security planning for the German concert and the number of security officials was increased substantially to 1,200, the police said.