Rome (CNN) Thousands of bones have been unearthed in two ossuaries discovered in the Vatican City, as part of an ongoing search for clues into the disappearance of a 15-year-old girl more than three decades ago.

Emanuela Orlandi, who was the daughter of a prominent Vatican employee and lived within the walls of the holy city, disappeared in the summer of 1983 while on her way home from a music lesson in central Rome.

Emanuela Orlandi

The mystery surrounding Orlandi's disappearance gripped Italians for more than three decades, and inspired conspiracy theories involving everyone from mobsters to international terrorists, and the highest echelons of the Vatican.

Interest in the case was renewed in summer last year, when the Orlandi family received an anonymous tip, hinting that Emanuela's remains may be located in the tombs of Princess Sophie von Hohenlohe and Princess Charlotte Federica of Mecklenburg at the Teutonic Cemetery.

Thousands of bones were found in two ossauries discovered at the Teutonic Cemetery in Vatican City.

The family had received an image of a sculpture and an instruction to "look where the angel is pointing." This led them to the Teutonic Cemetery, which is located adjacent to the grand Saint Peter's Basilica and is typically reserved for the burials of German-speaking Catholics.

After the Vatican agreed for forensic investigators to open the tombs on July 11, no human remains nor traces of coffins were found. The Vatican indicated that the remains of the princesses may have been removed during renovation work on the cemetery and surrounding buildings in the 1960s and 70s.

Nevertheless, two ossuaries -- chambers in which bones of the dead are stored -- were uncovered during their investigations beneath the floor of an area inside the Teutonic College.

Investigators subsequently discovered "thousands of bones" in the chambers, which are believed to correspond to "dozens of people," according to Giorgio Portera, a geneticist appointed by the Orlandi family.

Pope John Paul II with Emanuela Oralndi (pink jumper, center), and (from right) her brother Pietro, father Ercole, and mother Maria.

DNA analysis will now take place on each set of remains, but Vatican spokesman Alessandro Gisotti said the precise data will have to await "morphological evaluations next Saturday."

"It must be considered that many of the bones being dated are shattered and therefore this increases the number present, many of which are small," Gisotti told CNN. "This means that there may be more fragments of the same bone structure."

While the origins of the bones remain unknown, Emanuela's brother, Pietro Orlandi, 60, said the investigation into the ossuaries had been "a great satisfaction."

"In the ossuaries, there shouldn't be any recent bones, so if there are, even if it's not Emanuela Orlandi, it will be a problem for the Vatican," he told CNN. "There are hundreds, thousands of bones and now the Vatican is classifying them by age and will investigate the more recent ones.

Pietro Orlandi says that the investigation into the ossuaries has been a "great satisfaction."

"To think if she was buried in the ossuary all these years, just 200 meters from our house, it would be devastating."

He added that it is important for an independent expert to investigate the bones to ensure the objectivity of the results.

"The Vatican doesn't want this out and doesn't want to be seen in this way, but finally I feel like they have taken a step back and we have moved a step forward," he said.

The Vatican responded in a statement, according to Reuters, saying that it is "once again showing its openness towards the Orlandi family" in agreeing for investigations to take place in the Teutonic Cemetery, even when only based on an "anonymous report."