"During restoration works in a space annexed to the Apostolic Nunciature of Italy. fragments of human bone were found", the Vatican said in a statement, in reference to the diplomatic office of the Holy See in Rome.
The statement did not mention Orlandi - the daughter of a Vatican employee - by name, but the find raised immediate speculation about the girl's disappearance, which remains one of the Holy See's most enduring mysteries.
Rome's chief prosecutor is working to identify the bones found during renovation work at the Vatican property in Rome's Parioli neighborhood, the Vatican said Tuesday.
An investigation is already underway to determine the age and gender of the remains.
The family's lawyer said: "We're waiting to understand the details of the discovery, such as when the bones were found, who found them, gradually we should understand better what happened". The teen disappeared after leaving her family's Vatican City apartment to go to a music lesson in Rome.
Policía se suicida tras asesinar amigo de un disparo en la cabeza
Por su parte, el joven de 20 años fue trasladado de forma inmediata al hospital, lamentablemente murió poco tiempo después. Flavio al bajarse del automóvil y ver lo que había ocurrido, regresó al auto y con un balazo se mató .
Theories have circulated that the then 15-year-old was kidnapped by an organised crime gang to put pressure on Vatican officials to recover a loan.
Another claim was that she was taken to force the release from prison of Mehmet Ali Agca, the Turk who attempted to assassinate Pope Jean Paul II in 1981.
Despite Miss Orlandi's brother, Pietro, accusing the Vatican of silence and complicity in the case, the headquarters of the Roman Catholic church have said they have fully cooperated with police in the investigation.
Construction workers discovered human remains at the Vatican's embassy in Italy on Monday in what may mark a major potential breakthrough in the decades-old case regarding the disappearance of teenagers Emanuela Orlandi and Mirella Gregori in 1983.
Detectives say it is possible that the cases are connected.