Pope Francis has paid tribute to a priest who worked to keep youths away from the Mafia and was killed by mobsters during a visit to Sicily.

Francis says he flew to the Mediterranean island on Saturday morning to mark the 25th anniversary of the assassination in a Palermo slum of a “martyr priest”, the Rev Giuseppe “Pino” Puglisi – who was beatified in 2013.

The day-long visit to honour a priest who encouraged young people in a poor Palermo neighbourhood to spurn Cosa Nostra comes as the Catholic church is battered by revelations that many priests and bishops sexually abused children or protected abusers.

Pressure is building on Pope Francis to say what he knew about the sexual misconduct of US prelate Theodore McCarrick, who recently was stripped of his cardinal’s rank by the pope.