The tram derailed near Porta Venezia and crashed into a building. Several people were hit by the runaway tram and many were reportedly trapped under it.
Police say a man who was hit has died and that nearly 40 people have been injured, Italian media report.
It is not clear how many people are still trapped under the tram. The accident occurred during rush hour and the tram was reportedly full, according to Rai. It is unclear how the accident happened, but according to the newspaper Corriere della Sera, the brand-new tram was traveling at high speed.
