A Carabinieri bomb squad detonated the device, but it did not appear to contain any explosive material. The device turned out to be a tin can half filled with paint thinner, with two electrical wires running from a 9-volt battery, ANSA said. Tourists sounded the alarm after noting a suspicious package on the second level of the ancient Roman arena, ANSA said.

Rome police reached by telephone could not immediately confirm the incident.