A Vatican prosecutor said today that he has found new evidence that needs “further investigation” in the case of the disappearance of a 15-year-old schoolgirl 40 years ago.

On June 22, 1983, Emanuela Orlanti, the daughter of an usher who worked permanently at the Vatican, left to attend a music lesson in Rome and never returned home. Her disappearance is one of Italy’s longest-running mysteries.

The case again attracted the attention of the whole world on the occasion of the series “The Vatican Girl” that was broadcast last year on the Netflix platform.

Prosecutor Alessandro Didi announced in January that he would reopen the older, inconclusive investigation after inheriting the file from his retired predecessor. Today, he said his team had reviewed all available evidence and spoken to people who worked in “certain services” four decades ago, confirming that “certain evidence needs further investigation”.

In his statement, Didi said he had recently given his findings to Italian prosecutors to decide the best course of action. The Vatican noted that Didi will continue to investigate the case and understands the family’s long-term suffering.

In April, Pope Francis publicly criticized Orlandi’s brother for playing on public television the recorded statement of a gangster who said that girls were being taken to the Vatican to be sexually abused and that the then-pontiff, John Paul II, knew about it.

The brother, Pietro Orlanti, said today that he would stage a protest in St. Peter’s Square on Sunday, the day Francis blesses the faithful. “I told everyone to bring a picture of Emmanuela with them,” he told RAI radio station. “I’m doing it because I really hope that (the pope) can give us some words of hope.”

Many theories have been put forward for Emanuela’s disappearance: one of them linked her to the attempted assassination of Pope John Paul II, another that she was kidnapped by the underworld of Rome, a third that she fell victim to a group of pedophile priests.