Some former priests, mostly Franciscans, took part in the atrocities themselves. Miroslav Filipović was a Franciscan friar (from the Petrićevac monastery), who joined the Ustaša army on 7 February 1942 in a brutal massacre of 2730 Serbs of the nearby villages, including 500 children. Filipović became Chief Guard of Jasenovac concentration camp, where he was nicknamed ""Fra Sotona"" by the camp inmates. He was hanged for his war crimes in his Franciscan robes.