The Krabbeplas near Vlardingen was closed for swimming on Wednesday after the discovery of thousands of dead fish in the lake. They likely died due to the heat, RTV Rijnmond reports.
Passersby saw the dead fish floating in the lake on Wednesday morning and called Staatsbosbeheer, which decided to close down the area around the lake. Visitors were already warned against swimming in the lake due to blue-green algae.
Samples were taken from the lake, to find out why the fish died.