Forensic experts have begun examining bones from a Vatican cemetery as part of an investigation into the disappearance of a 15-year-old schoolgirl more than three decades ago.

Emanuela Orlandi, the daughter of a Holy See clerk, was last seen in 1983 after leaving her family's Vatican City apartment to go to a music lesson in Rome. Theories abound about what may have happened to her.

Earlier this year, the Orlandi family received an anonymous tip that Emanuela's body might be hidden near the 19th century tombs of two German princesses in the Vatican's Teutonic College cemetery.

An exhumation of the graves yielded no results. Instead, it led to more questions. Both tombs were empty, with no trace of Orlandi, or the remains of the princesses who were supposedly laid to rest there.

Read more: Vatican: Police probe bones unearthed at Rome embassy

Who do the bones belong to?

Church officials said the remains of Princess Sophie von Hohenlohe and Princess Carlotta Federica of Mecklenburg, who died in 1836 and 1840 respectively, may have been moved during structural work in the cemetery.

The Vatican announced last week that it had since located two sets of bones in burial chambers in the adjoining Pontifical Teutonic College. Those bones were extracted on Saturday and will now undergo DNA testing to try to establish who they belong to.  

In a statement, the Vatican said it was "not possible, for the moment, to predict how long it will take for the morphological analysis of the remains to be completed."

Read more: Vatican opens probe into missing girl Emanuela Orlandi

Emanuela's brother, Pietro Orlandi, 60, whose 88-year-old mother still lives within the Vatican walls, told Agence France-Presse he hoped his sister was still alive.

"I will have to carry on. Until I find Emanuela, it is my duty to seek out the truth," he said.

There are several theories about what may have happened to the missing teenager. Some believe she was abducted and offered in exchange for the freedom of Mehmet Ali Agca, a Turk jailed for attempting to assassinate Pope John Paul II in 1981. Others claim she was taken by mobsters to pressure the Vatican to recover a loan.

One conspiracy theory speculated that crime boss Enrico De Pedis was involved in her kidnapping, and that the teen may have been buried alongside him in a Rome basilica. His tomb was opened in 2012 but DNA tests turned up no new clues.

nm/jm (AFP, Reuters)

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