Priests held a special "cleansing" ritual at the main altar of St. Peter's Basilica, which is also used by Pope Francis, after the space was desecrated Sunday by a man who appeared there naked to protest the war in Ukraine.

At the prayer mass led by Cardinal Mauro Gambetti the man, a Polish citizen, stripped and stood in front of the basilica's altar on Thursday. On his back was written "save the children of Ukraine".

Vatican security handed over the protester to the Italian police, who detained him and in the meantime deported him from Italy.

Gambetti said the man had made a "wrong and inappropriate gesture, which is regrettable", in order to draw attention to the victims of the war.

A source from the Vatican states that during the incident, the protester self-inflicted scratches on his body.