Pope Benedict XVI on Wednesday mourned the death of a Roman Catholic priest killed in Turkey. Turkish police have been questioning a 16-year-old suspect who has confessed to the killing, saying it was retribution for the publication of cartoons depicting the Prophet Muhammad.

Thousands of pilgrims gathered in the Vatican's Paul VI Hall for the Wednesday general audience broke into applause when Pope Benedict XVI spoke of Father Andrea Santoro, the priest killed on Sunday in Turkey.

The 60-year-old priest was fatally shot while he was praying after celebrating mass at his parish church in the city of Trabzon on the Black Sea. Turkish police have arrested a 16-year-old boy.

The boy told police he killed the priest to avenge the publication in European newspapers of cartoons depicting Islam's Prophet Muhammad as a terrorist.

The suspect said he needed to kill someone in a Catholic Church. He said he had been totally shocked by the cartoons.

Pope Benedict said Wednesday he hoped the death of Father Santoro would promote dialogue among religions and peace among peoples. He also said he was particularly moved when he read a letter he had just received from the priest.

"I read the letter with deep emotion," the pope said, "it is a mirror of his priestly soul and of his love for Christ and mankind and of his commitment to the little ones."

The pope said the letter was a moving witness of love and fidelity to Christ and the Church. He said it would be published in the Vatican's newspaper.

The body of Father Santoro has been returned to Italy, where many remember him as a kind priest, always willing to help. His funeral will be held in the Basilica of St. John Lateran in Rome on Friday. It will be conducted by Cardinal Camillo Ruini, the pope's vicar for Rome.