Pope Francis on Sunday defended St. John Paul II against a recent accusation that the Polish pope secretly visited women at night.

Speaking to the public on Divine Mercy Sunday, a day established by Pope John Paul II in 2000, Pope Francis called the insinuation “unfounded and offensive.”

“Certain that I interpret the feelings of the faithful throughout the world, I address a grateful thought to the memory of St. John Paul II, at this time the object of unfounded and offensive conjectures,” he said.

Pope Francis greeted groups that promote the spirituality of Divine Mercy after leading the Regina Caeli, a Marian antiphon prayed during the Easter Season, from a window overlooking St. Peter’s Square on April 16.

Pietro Orlandi, the brother of Emanuela Orlandi, a 15-year-old girl and Vatican citizen who went missing 40 years ago, insinuated this week that John Paul II secretly left the Vatican at night to engage in immoral behavior.

Orlandi made the statement April 11 on the Italian television program Di Martedi, on which he appeared with his family’s lawyer, Laura Sgrò. Neither would disclose the source of the rumor.

Cardinal Stanisław Dziwisz, who was John Paul II’s personal secretary for over three decades, said this week the rumors were “vile insinuations” and “false from beginning to end.”

Orlandi, who has been trying to get answers to his sister’s disappearance for 40 years, met with the Vatican’s chief prosecutor for eight hours on April 11.

Alessandro Diddi, prosecutor for the Vatican City State, said that Pope Francis had granted him “maximum freedom of action to investigate [Orlandi’s case] on a broad scale without conditions of any kind.”

“Pope Francis tenaciously pursues the desire for absolute transparency, the search for truth and purification,” Diddi said in an interview with the Italian newspaper Corriere Della Sera.

Emanuela Orlandi was the 15-year-old daughter of Ercole Orlandi, an envoy of the Prefecture of the Pontifical House and a citizen of Vatican City State. Her disappearance on June 22, 1983, after leaving for a music lesson in Rome, has been one of Italy’s biggest unsolved cases and the subject of speculation for decades.

The case was also the subject of a Netflix true-crime docuseries, “Vatican Girl: The Disappearance of Emanuela Orlandi,” which came out last year. The final episode of the series puts forward a theory that the Vatican was somehow involved in the disappearance.

The Vatican has always denied having any role in the girl’s vanishing and has cooperated with other investigations into the disappearance in recent years.

In January, the Vatican’s prosecutor opened a file to further investigate Emanuela Orlandi’s disappearance at the request of her family.

According to Vatican spokesman Matteo Bruni, Diddi’s April 11 meeting with Pietro Orlandi and lawyer Laura Sgrò, which was requested by Orlandi, served as an occasion for Orlandi to “make his own statements and to offer any information in his possession to the file opened by the Vatican promoter of justice in January.”