At least 524 captives (including 150 women with dozens of children) were shot by the NKVD and buried in several mass graves dug by the prisoners themselves in a small gorge outside of the city.

Some of the earlier victims were killed in the infamous NKVD prison in Stanisławów; others were brought to the site ahead of time in order to dig mass graves prior to their own execution.

[2] In 1970, following the Radio Liberty broadcast about Dem'ianiv Laz, the site's landscape was changed by heavy machinery to hinder any future attempts to excavate it.

[3] Despite these efforts, in 1989 remains of more than 500 men, women and children were uncovered during excavation performed by a local branch of the Memorial society.

After the invasion in 1941, the German authorities under SS-Hauptsturmführer Hans Krueger perpetrated another Aktion against Polish intelligentsia called the Czarny Las Massacre.