A former Vatican employee is demanding 100 thousand euros for the safe return of an extremely rare letter handwritten by Michelangelo, along with another letter he signed, which disappeared from the archives of Saint Peter’s Basilica nearly 20 years ago.

On Sunday, the Italian daily Il Messaggero broke the story of the ransom demand, as well as the 1997 theft, which had never been made public. The story also elicited a response from Vatican spokesman Father Federico Lombardi, who confirmed the essentials.

While the article spoke of only one stolen letter, Father Lombardi said that two letters had actually been taken.

In his statement, Lombardi said that in 1997, the archivist of Saint Peter’s, Sister Teresa Todaro, discovered that two letters, one handwritten by Michelangelo and the other bearing his signature, had disappeared. At the time, Todaro informed her superior, Cardinal Virgilio Noè, who was archpriest of the Basilica.

Lombardi also confirmed that the current archpriest, Cardinal Angelo Comastri, “has received a proposal to reacquire the documents at a certain price.” The spokesman said that, “naturally” the cardinal refused, since the documents were stolen.

Lombardi also said the Vatican police force is investigating the case together with the Italian police.

One of the documents is considered extremely precious because it is a rare example of a letter completely handwritten by Michelangelo Buonarroti, the Tuscan architect and artist responsible for the dome over St. Peter’s Basilica, the statue of the Pietà, and the painted ceiling and Last Judgment in the Vatican Sistine Chapel. Michelangelo usually dictated his letters, only appending his signature to the texts.

Reports suggest that the thief needed familiarity with the rooms adjacent to the basilica where the documents of the building, from 1506 onwards, are stored. The thief would have needed to know where to look and how to navigate in an area that is off-limits to almost everyone.

Follow Thomas D. Williams on Twitter @tdwilliamsrome.