I recently acquired the photo below which features a group of former Polish forced labourers standing in front of a large sign board that was put up by US liberation forces to commemorate the Gardelegen war crime in which 1,016 slave laborers were burned alive in a barn or shot to death whilst trying to escape the conflagration. The photo is dated on the reverse 10 May 1945—a little over one month after the German atrocity occurred.
Below: a closeup of the sign board in English. The man on the left can be seen still wearing his mandatory letter "P" diamond shaped patch on the right on his jacket that identified Polish forced workers from the German population.
The war crime was discovered two days after it happened by F Company, 2nd Battalion, 405th Regiment, U.S. 102nd Infantry Division when the U.S. Army occupied the area.
Above: Some of the victims of the Gardelegen war crime. A further collection of photographs can be found at the USHMM: Gardelegen war crime
Above: Under the direction of an American soldier, German civilians from Gardelegen carry wooden crosses to the site where they were ordered to bury the bodies of concentration camp prisoners killed by the SS in a barn just outside the town.
The official website of Gardelegen city:
CITY GARDELEGEN - History / Memorial Place / Historic events