Mateusz Morawiecki laid flowers at the so-called Wall of Death in the former Rakowiecka Prison in Warsaw to mark 72 years since the death of Captain Witold Pilecki, known as the “Auschwitz Volunteer”.
Also taking part in the ceremony was Pilecki’s daughter, Zofia Pilecka, who earlier met with President Andrzej Duda.
The Wall of Death was a site where Poland’s communist-era regime executed prisoners.
"The vastness of the harm and of the crimes that Polish patriots experienced will remain in our memory, which we must cultivate so that it does not become overgrown with weeds," Morawiecki wrote on social media.
Monday marked the first International Day of Heroes of the Fight against Totalitarianism, established by the European Parliament last year to mark the anniversary of Pilecki’s execution.
Pilecki was a World War II resistance fighter who alerted the world to the horrors of Nazi Germany’s deadliest Holocaust site.
He volunteered for a secret undercover mission: getting himself arrested by the Germans and sent to the Nazi German death camp of Auschwitz in order to smuggle out intelligence.
Pilecki barely survived almost three years of brutality, disease and starvation. He escaped from Auschwitz in 1943, reached Warsaw and fought in the 1944 Warsaw Uprising.
After the war he was captured by Poland’s communist security services and executed in 1948.