They call themselves the last generation, "Letzte Generation" and have, among other things, blocked access roads and traffic tunnels.
In the last week, German "klimakleber", or "climate glues", have carried out new and spectacular actions.
On two occasions they have entered airports, in Berlin and Munich respectively.
Berlin's airport was the furthest, says SVT's European correspondent in Morgonstudion.
- There they got to the runways and got stuck, and blocked them so that 20 departures had to be cancelled, says Christoffer Wendick.
He continues:
- Many here in Germany saw it as having crossed yet another line for the type of illegal actions that one is prepared to do in order to create debate about the climate.
Recently, a woman in Berlin died after she had a serious bicycle accident while two activists were carrying out an action, unknowingly blocking the path of an emergency vehicle.
The doctor who cared for the woman has stated that it did not cause the death, but the event that drew attention has now become a legal matter.
Demand for tougher penalties
The security police are said to be concerned about radicalization within the environmental movement.
The German terrorism expert Bettina Röhl has told the newspaper Bild that it is on the way to becoming extremist.
At the same time, politicians warn of environmental terrorism and want to toughen the punishment for radical climate protests.
However, the tones vary somewhat based on the political scale.
- Those who are furthest to the right and in the middle are the most critical of this.
Those who are out on the left, the left party (Die Linke) for example, have shown more understanding, at least for the frustration and anxiety that these people express in their actions, says Wendick.
In the clip above, Christoffer Wendick tells more about the ongoing discussion and concerns about the climate actions in Germany.