Twenty dolphins were slaughtered on Friday in the southwestern Japanese town of Taiji, marking the beginning of the cove’s infamous annual dolphin hunt, according to local media, Agence France-Presse reports.

The hunt has attracted global condemnation since 2009, when it was featured in the Academy Award-winning documentary The Cove, which depicted how fishermen round up some 1,000 dolphins a year to sell to marine parks or kill for meat. The slaughter turns the cove red with blood. In 2015, the Japanese Association of Zoos and Aquariums banned the buying and selling of dolphins from the controversial hunt, after protests and pressure from the World Association of Zoos and Aquariums, a global industry organization.