THE Carabinieri of Naples they released a 3D reconstruction made by the geologist Gianluca Minin (president of the Galleria Borbonica and among the leading experts on the Neapolitan subsoil) who shows the network of underground tunnels dug to score the robbery of the Credit Agricole bank of Piazza Medaglie d’Oro, in the Arenella district of Naples, which began at 12 on Thursday 16 April and concluded in the afternoon after the liberation of 25 hostages. The three-dimensional map, created with a portable lasershow i 12 meters dug by hand in the tuff between the tunnels of the sewer system and used by robbers to emerge into the bank vault and disappear into the city sewers.
The dynamics of the robbery at Credit Agricole dell’Arenella
Around 12.15pm of April 16th at least three people with their faces covered by balaclavas wearing movie actor masks (including The Rock) broke into the bank branch, where they were 25 people between customers and employees. The robbers, armed with pistols, held everyone hostage in a room that looked out onto the street through armored glass, while people flocked to Piazza Medaglie d’Oro. Carabinieri of the API (Emergency Response Rates) in riot gear ei Fire Brigade following a call to 112.
After about three hours, around 3pm the Fire Brigade freed all the hostages by breaking the armored glass window of the bank. At 4.45pm i also attended GIS Carabinieri (Special Intervention Group), arrived from Livorno by helicopter, who entered the branch with the API. It is at this point that the police discovered a hole in the floor of the vault, approximately 50 centimetresfrom which the robbers escaped by entering the sewer system after stealing the contents of approximately 40 safesthe value of which is unknown to the bank.
According to initial reconstructions, while the group of robbers who entered the branch used the hostages as a diversion, a second group of 5 or 6 robbers he would have emerged into the vault (whose anteroom floor was not armored) through a net of small tunnels dug by hand between the tunnels and would have had plenty of time to steal the safes. The same underground route was also used by the masked group to disappear into the labyrinth of the city sewer system.
3D mapping of the underground tunnels dug up to the bank vault
The day after the robbery Gianluca Minin inspected and mapped the route used by the gang. It is a complex, long journey 12 meters and wide between 70 and 90 centimeterscompletely devoid of supports or coverings and therefore particularly risky to travel. The route is located approx 4-4.5 meters deep and reaches the vault thanks to a vertical section approximately 5 meters long.
The whole thing was dug by handwithout tools, in all likelihood to avoid suspicious noises: a preparatory work which therefore required a very long time and above all a in-depth knowledge of the city’s subsoil. The sewage system in that area is indeed extremely complex: during the inspection Minin encountered about ten crossroads in a 12 meter long stretch.
In short, the situation clearly shows that the thieves were not improvisedbut highly trained and who had planned the robbery down to the smallest detail, also running huge risks due to possible collapses of the underground route. The fact that the thieves knew that the floor of the vault was not armored and that some of the safes were not stored in safes also led investigators to hypothesize the presence of a basemanthat is, a “mole” perhaps inside the branch of the credit institution who knew the latter closely and what was happening inside it.
The importance of the subsoil geology of Naples in the robbery
As explained by Minin, the network of tunnels exploited by the robbers is that of the sewer system and not of the Underground Naplesbut we still find ourselves in the same geological context: the subsoil of the Neapolitan capital in fact presents a layer thicker than 100 meters made up of tuff emitted during two large volcanic eruptions.
The first was theeruption of the Campanian ignimbritethe most violent that occurred in the Mediterranean basin in the last 200,000 years with a. It dates back to approx 39,400 years agowhen i Phlegraean Fields they issued something like 150km3 of magma. The pyroclastic materials produced by the eruption and deposited on the ground can then aggregate and solidify (also with the help of water) in tuffan igneous rock. It is estimated that this eruption covered a good part of Campania with a blanket of tuff up to 500 mm thick 100 meters.
The second was theeruption of Neapolitan yellow tuffoccurred 15,000 years agoalso attributed to the Campi Flegrei, second in violence only to that of the Campanian ignimbrite. It is estimated that he issued up to 40km3 of magma and deposited a further layer of yellow tuff above that of the eruption 39,000 years ago.
Tuff is a material soft, porous and easily workablewhich makes Naples a city with a unique subsoil in Europewith a water and sewage network that intersects, overlaps on several levels and connects to the tunnels of Napoli Sotterranea. The characteristics of tuff in fact make it a material – as well as being useful for construction – particularly suitable for the construction of tunnels and passages: this material, produced by complex volcanic geology of the area, which allowed the gang of robbers to carry out such a complex heist.
