One of Germany's biggest music festivals has been evacuated by police due to a possible terrorist threat.

Key points: All those attending were asked to leave the concert, head to nearby camping grounds

All those attending were asked to leave the concert, head to nearby camping grounds Suicide bombing at Manchester concert led to changes in security planning for German event

Suicide bombing at Manchester concert led to changes in security planning for German event Last year, Rock am Ring was cancelled after lightning strikes injured 80 people

The organisers of Rock am Ring said they were temporarily interrupting the event as a precautionary measure following advice from authorities.

"Due to a terror danger situation, we told the organiser to temporarily stop the concert as a precaution," police in the nearby town of Koblenz said in a statement.

Tens of thousands of people usually attend the annual three-day open-air event, which is held near the western city of Nuerburg.

Festival-goers were asked to leave in a controlled and calm manner as they streamed out of the venue.

"The organiser of Rock am Ring, working closely with the security authorities, have ended ahead of schedule," the police statement added.

"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 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.

"We take all tips and suspicious incidents extremely seriously and investigate closely," the force added.

Last year, the third and final day of the Rock am Ring was cancelled after lightning strikes injured 80 people, some seriously.

ABC/Reuters