In Germany, tens of thousands of climate activists have turned up to protest at the country's biggest car show in Frankfurt, using the event as a platform to demand the car industry address its role in damaging the environment. Our correspondent Guy Henderson has more from Frankfurt.

The police were expecting them -- but didn't disperse them. Perhaps a thousand protesters - lining the entrance to Sunday's Frankfurt Motor Show. And calling for climate justice. 

"We have to act now. Our world is in danger. And the politics is either do nothing or not enough. So it's mandatory to take action".

Passing them occasionally - groups of cyclists calling for the same thing. 

"They will not change anything because they get money from the car lobby - so we have to be loud and say we want this change, or they will take us for fools". 

Members of the public - parents, children amongst them - may have underestimated their resolve. Some who tried to enter were forcefully pushed back. This man was injured. Police then bolstered their numbers And briefly tried to help Motor Show ticket holders through. That didn't go down well. Even with this paramedic. So - after some discussions - the demonstrators were once again allowed to hold the line.

GUY HENDERSON FRANKFURT "At least 15 thousand people turned out on the streets of Frankfurt on Saturday. On Sunday, there's a much smaller group, but one that had promised to actually disrupt the Motor Show. And they've done exactly that."

Visitors were left searching for another way in, at best puzzled - at worst annoyed. 

"These nitwits have no idea what they're talking about."

 Guy: "But there is an issue with climate change, isn't there?

"My personal opinion is the gasoline is too cheap."

All this left long queues at the side entrances, before some of them were blocked too. Inside numbers seemed lower. Though organisers have been reluctant to criticise.

ECKEHART ROTTER SPOKESPERSON, FRANKFURT MOTOR SHOW "We have some[thing] in common: both are wanting to save the planet. That means how can we reduce CO2 emissions."

It is the "how" on which they strongly disagree.