The blast is reported to have taken place in the eastern part of the city and to have been caused by a cherry bomb, a kind of spherical firework.
When police arrived at the scene, two people were injured by the blast, one of whom later died shortly after being taken to hospital. The victim was a 32-year-old man, Repubblica reported, and the other injured person a woman aged 43.
The woman has also been transported to hospital for treatment while police are investigating the blast.
Two parked cars were also damaged in the explosion and a gate of a nearby building torn off its hinges.