Unknown persons have daubed several swastikas on the grounds of the Buchenwald concentration camp memorial in Thuringia.
The graffiti were discovered on Thursday evening on two traffic signs in a memorial parking lot and on a site plan, the police in Jena reported on Friday.
The perpetrators also left other right-wing extremist symbols in black and yellow paint.
Despite immediately initiated search measures, the perpetrators could not be apprehended, according to the information.
The graffiti was removed immediately.
The police are investigating.
Most recently, memorial trees near the former concentration camp had been repeatedly damaged and destroyed.
The Buchenwald memorial commemorates the approximately 56,000 people who were killed there during the Nazi era.
In total, more than 76,000 men, women and children died at the hands of the Nazis in the Buchenwald and Mittelbau-Dora camps, which are also in Thuringia.
More than 340,000 people from all over Europe were deported to the camps and their satellite camps.
On April 11, 1945, the camp near Weimar was liberated by US troops.