(CNN) — Climate activist Greta Thunberg was arrested by German police on Tuesday. CNN affiliate N-TV reported that the activist took part in a protest against coal mine expansion in the western city of Lützerath.

Thunberg joined thousands of activists and protesters who took part in protests over the weekend against the demolition of a German village to make way for an expansion of the Garzweiler lignite coal mine owned by European energy company RWE.

Once the evacuation is complete, RWE plans to build a 1.5 kilometer perimeter fence around the village, blocking building entrances, streets and sewers for demolition.

Picture of police taking Greta Thunberg into custody.

Coal mining expansion is significant for climate activists. According to them, continuing to burn coal for energy will increase global warming emissions and go against the goals of the Paris Climate Agreement to limit global temperature rise to 1.5 degrees Celsius. Lignite is the most polluting type of coal, the most polluting fossil fuel.

Thunberg tweeted on Friday that she was in Lutzerrat to protest the mine expansion and called on others to join her.

Climate strike week 230. We are currently in Lützerath, a German village threatened with demolition for the expansion of a coal mine. People have been resisting for years. Join us at 12 or claim it at a local demonstration tomorrow #LützerathBleibt !#ClimateStrike pic.twitter.com/hGrCK6ZQew

— Greta Thunberg (@GretaThunberg) January 13, 2023

Throughout the month, there have been clashes between activists and police, while photos of protests have shown police using riot gear to disperse protesters. CNN previously reported that some of the protesters have been in Lützerath for more than two years, occupying houses abandoned by former residents who were evicted to make way for the mine.

More than 1,000 policemen participated in the evacuation operation this Tuesday. Most of the buildings in the village have already been vacated and replaced by bulldozers.

RWE and Germany’s Green Party reject claims that mining expansion will increase overall emissions, arguing that European caps could offset the extra carbon emissions. But several climate reports have made clear the need to accelerate clean energy development and move away from fossil fuels. Recent studies suggest that Germany may not even need the electricity from those additional coal mines. An August report Coal Transitions, an international research platform, found that although coal plants are operating at peak capacity until the end of this decade, they have more coal than they need from existing supplies.

This story has been updated with more information.