Local police said on Friday they suspected the man was part of a gang of four who allegedly planned to carry out the heist this weekend, when the Italian capital would be relatively quiet due to the Ferragosto public holiday.
The Carabinieri police’s press office told CNN that officers arrived at the collapsed tunnel on Thursday, after receiving reports that a man was trapped under the rubble.
Soon after they arrived they arrested two people suspected of trying to flee the area by car and, separately, a fourth man.
Rescuers spent eight hours freeing the trapped man, who remains under medical observation in the San Camillo hospital in Rome.
Lawyer Carmine Pascarosa, who is representing the two men arrested in the car, told CNN the pair had been charged with resisting arrest and were not presently under investigation for other crimes.
He said the two men denied involvement with the man rescued from the rubble. According to Pascarosa, he two men said they had been passing the area “by chance” when a man asked them for help and took them to a vacant shop that housed the entrance to the tunnel.
Once they realized what had happened, they called rescuers before leaving the scene, he added.
Pascarosa confirmed that a fourth person is being investigated and has been charged alongside the injured man in relation to the collapse of the tunnel.