(WB) Police in the German capital say vandals have damaged a memorial to gay victims of the Nazis.

The Associated Press on Monday said security guards at the memorial in Berlin’s Tiergarten park reported a window into which passersby can watch a video of a same-sex couple kissing had been painted over. Authorities told the Associated Press they have not identified any suspects in connection with the vandalism.

The Nazis between 1933-1945 systematically persecuted gay men.

Statistics indicate as many as 15,000 gay men were sent to concentration camps. Germany in 2002 pardoned up to 50,000 gay men who were convicted of Nazi-era crimes because of their sexual orientation.