Those unfortunate enough to board the Zuiderdam cruise ship departing Kiel in northern Germany on Sunday were met with a surprise: dozens of climate change activists in small boats blocking the departure port, carrying large banners that read, “Cruises kill climate.”

It took police and special forces hours to clear the demonstration and confiscate the protesters’ ships. Protesters with the Extinction Rebellion group then proceeded to jump into the water and swim in front of the cruise ship, all to fight the “catastrophic local and global consequences of cruises.”