Italy’s Carabinieri Command for the Protection of Cultural Heritage, a squad tasked with combatting crimes relating to art and antiquities, has revealed some of the tactics it employed to discover an underground network of tunnels that were used for the illegal looting of an 11th-century church that lies beneath a house in Naples.

The exceptional medieval church sits some 25 feet below street level and, so far, a well-preserved frescoed apse has been uncovered. It contains an image of Christ enthroned and surrounded by simple decorative features. The floor, only partly revealed, is made of white marble slabs.

Thanks to the Carabinieri, this historically significant find, previously unknown to archaeologists and art historians, has been rescued for the Italian public and for legitimate research.

The semicircular frescoed apse of an 11th-century church discovered underground in Naples. Photo courtesy Carabinieri TPC.

The church was discovered by a gang of tombaroli, or tomb raiders, allegedly led by a local who has been described only as an “entrepreneur.” This man, who is still under investigation, owns two apartments at street and basement level in the building above the church. This is just one of numerous premises across Naples from which, investigators believe, he was operating a well-organized network of illegal excavations via underground tunnels. Among other properties that the Carabinieri inspected was one with passageways connecting to the foundations of an 18th-century palace.

Through this system, the alleged ringleader and his gang were amassing precious artifacts that may eventually have been sold. Some 10,000 fragments of Roman and medieval pottery have been recovered from the entrepreneur’s possession, as well as 453 undamaged artifacts, including terracotta oil lamps and pipes, amphorae, and Roman and medieval coins.

So how did the Carabinieri’s dedicated squad manage to bust the complex looting operation? The gang were at work for several months before they were discovered, and they used everyday ambient noise during the working day to disguise their loudest activity. Unbeknownst to the perpetrators, however, they were being observed by the squad, which had staked out the building and tapped the alleged leader’s phone.

Medieval artifacts seized by the Carabinieri in Naples. Photo courtesy Carabinieri TPC.

“Keeping an ear to the ground is essential,” the squad’s chief in Naples, Massimo Esposito, told the Guardian. “We were informed about anomalous construction activity, and intuited that it could be an illegal excavation after records showed there was no public or private works happening in or near that building to justify such activity.”

According to the same report, the suspected leader of the operation likely realized there could be an archaeologically valuable site below his home when another church was accidentally discovered nearby during construction work.

Carabinieri at the site in Naples. Photo courtesy Carabinieri TPC.

His intentions may have been criminal, but thanks to the alleged perpetrator’s initiative, the medieval church may one day be made accessible to the public. Esposito confirmed that “this is always the ultimate goal.”

The Carabinieri’s squad had a busy year in 2024. Last month, they arrested four people involved in an international trafficking ring in Puglia and Lazio. In November, they recovered precious artifacts worth $8.5 million that had been stolen from an Etruscan necropolis in Tuscany.