The new communist government took advantage of existing anti-tank trenches, dug around Celje by the retreating German army, by using them as mass graves.
At the nearby concentration camp at Teharje, some 5,000 Slovenians, hundreds of them minors, were murdered within two months after the end of the war, again without trial.
Furthermore, refugee trains carrying German civilians from the Rann triangle area were halted near Celje on 5 August 1945 and their passengers sent to a concentration camp at Teharje.
[citation needed] After the camp was closed in 1950, the local authorities established a large industrial dump over the graveyard there, concealing the evidence of killings under a mound of toxic waste.
In the mid-1970s, 30 years after crimes, the local authorities built preschools, schools, apartment blocks, halls and other structures on top of the mass graves.