Berlin police say activists protesting rising rents and gentrification in the German capital have occupied nine vacant buildings.

The dpa news agency reported Sunday that apartments in the trendy Kreuzberg, Neukoelln and Friedrichshain neighborhoods were among the buildings taken over.

The protesters hung banners out windows and tweeted using the hashtag #besetzen, German for "occupy."

Real estate prices and rents have skyrocketed in Berlin in recent years, creating affordability pressures that have been the subject of demonstrations for stricter rent control and more affordable housing.

The building occupiers issued a statement saying they are staging a "radical intervention against the principle of speculative vacancies."

It was not immediately clear how many activists were involved or how long they planned to stay the buildings.