Rome -- The tiny, 1,200-year-old Teutonic Cemetery is the only graveyard inside the walls of Vatican City. The cemetery just behind St. Peter's Basilica is the final resting place of royals, cardinals, artists. Until Thursday, there had been a brief hope that just maybe, the remains of a teenage girl who disappeared 36 years ago might also be inside one of the tombs.

On Thursday the Vatican opened two 19th century graves in the cemetery to let forensic experts look for the remains of Emanuela Orlandi. She was the 15 year-old-daughter of a Vatican bank employee whose family lived inside Vatican City. Orlandi was last seen at a bus stop in central Rome after leaving a flute lesson on June 22, 1983.

People open tombs in a cemetery on the Vatican's grounds to test the DNA of bones to help solve the 36-year-old disappearance of a teenage daughter of a clerk in the Holy See, in the Vatican July 11, 2019. VATICAN MEDIA/REUTERS

A new mystery?

The mystery of her disappearance has gripped Italy ever since. Now it may have sparked a brand new mystery.

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Two tombs were opened; the "Tomb of the Angel," of Princess Sophie von Hohenlohe who died in 1836, and the tomb of Princess Carlotta Federica of Mecklemburg, who died in 1840. Members of their families, Orlandi's, and forensics scientists and Vatican police were all present as the tombs were unsealed.

In a statement released after just a couple hours of work, Vatican spokesman Alessandro Gisotti said the operation had "produced negative results: no human findings or funerary urns were found" in either of the tombs -- neither any remains appearing to belong to a teenager from the 1980s, nor any belonging to the 19th century princesses.

A Feb. 13, 2013 file photo shows the Teutonic Cemetery in the courtyard of the Collegio Teutonico, as seen from atop St. Peter's Basilica at the Vatican. Getty

"Careful inspection of the tomb of Princess Sophie von Hohenlohe has unearthed a large underground compartment of about 4 meters by 3.70, completely empty," Gisottti said. "Subsequently, the opening of the second tomb-sarcophagus took place, that of Princess Carlotta Federica of Mecklemburg. Inside it, no human remains were found. The family members of the two Princesses were informed of the results of the research."

"The tombs are empty. We are all amazed," Orlandi family lawyer Laura Sgro said Thursday after the fruitless opening of the tombs.

Another dead-end

Orlandi's mother still lives in Vatican City, close to the Teutonic Cemetery. After searching for Emanuela incessantly for three decades, the family's lawyer had said they wouldn't be happy "if they find Emanuela's corpse just 200 yards from their home."

Giovanni Arcudi, a forensics expert and professor at Rome's Tor Vergata University, led the team that was supposed to have been exhuming skeletons on Thursday and then examining them to verify who they belonged to.

Arcudi's team had also planned to collect samples for DNA testing, but in the end he had no remains to work with.

Orlandi's family has been chasing clues on her disappearance for decades, and conspiracy theories abound. Because the family lived inside the Vatican walls, many of the rumors involve the Vatican itself: that she was murdered in connection to the Vatican bank scandals of the 1980s; that she was kidnapped to barter for the freedom of a man who attempted to kill Pope John Paul II; that she was kidnapped as part of a sex slavery ring inside the Vatican. So far there has been no solid evidence in the case at all.

Thursday wasn't the first time a grave has been opened to search for the teenager's remains. After persistent rumors that her body was concealed in the grave of a Roman mobster, police opened his tomb in 2012. They found nothing that didn't belong there.

Last summer, the family received yet another anonymous tip.

Tombs in a cemetery on the Vatican's grounds are seen before being opened to look for any remains linked to the 36-year-old disappearance of a teenage daughter of a clerk in the Holy See, in the Vatican, July 11, 2019. VATICAN MEDIA/REUTERS

"I received a letter with a picture in it," Sgro told CBS News. "The letter said: 'If you want to find Emanuela, search where the angel is looking.'" The photo was of a marble statue of an angel that looks down on the German princesses' tombs in the Teutonic Cemetery.

Sgro said the family went to the Teutonic Cemetery and quickly found the "Tomb of the Angel," and they noticed something that seemed to be amiss.

"The tomb had obviously been recently opened, there was new cement on it, but we didn't know why or when, we were given no information," Sgro told CBS News. In February, they petitioned the Vatican Secretary of State to permit the tombs to be opened. Last week a Vatican tribunal granted the request.

The Vatican confirmed in a statement that the "grave indicated by the lawyer of the Orlandi family is, in fact, the one with the angel holding in his hands an open book with the inscription "Requiescat in pace" (Rest in peace)" -- the so-called Tomb of the Angel, which should only have contained the remains of Princess Sophie.

A man is seen on a ladder as people open a tomb in a cemetery on the Vatican's grounds to test the DNA of bones to help solve the 36-year-old disappearance of a teenage daughter of a clerk in the Holy See, in the Vatican July 11, 2019. VATICAN MEDIA/REUTERS

The Vatican tribunal ordered both tombs to be opened, however, as they are immediately next to each other and they have "similar mausoleums -- in order to avoid possible misunderstandings about which grave is the indicated grave."

Vatican officials said they would go back to records to try and figure out what became of the princesses' remains. There were renovations carried out in the cemetery at the end of the 1800's, and then again in the 1960s and 1970s.