Greta Thunberg joins thousands in protest against coal mine expansion in Germany.
Lützerath, a village set to be demolished, is at the center of the protests.
Thunberg & protesters demand to stop the mine expansion to meet climate targets.
The mine is one of three open-pit coal mines responsible for 20% of Germany's emissions.
Many villages have been demolished in the past to make way for the mines.
Lützerath has been a focal point of protests for a decade.
Germany originally committed to reducing emissions by 2030 but failed due to reliance on coal.
Climate activists continue to push for change in Germany's energy policies.
Thunberg's arrest brings attention to the urgent need for action on climate change.