AN explosion on an Italian overpass claimed at least two lives and injured dozens of others after a tanker exploded and caused part of the road to collapse.

The deadly accident occurred near Borgo Paginale, to the west of Bologna.

Footage from the scene in the northern city showed a huge fireball shooting into the sky. Plumes of black smoke could be seen from many kilometres away.

Terrorism fears were quickly dismissed by local police, who said the cause of the blast was a tanker that exploding after a collision. The tanker was believed to be carrying liquefied petroleum gas.

As many as 70 people were injured, some with serious burns.

Many of the victims had been hit by flying glass when windows in nearby buildings exploded, a local television network reported.

Terrified residents reported their houses “shook” when the vehicle exploded at around 12.50pm.

The Italian news agency ANSA reported the explosion was caused by an accident involving the tanker, which exploded upon impact.

Cosa sta succedendo? Esplosione in corso a #bologna pic.twitter.com/nDEjgRt8bk — Biagio Tozzi (@biagiotozzi) August 6, 2018

The force of the explosion caused raised part of the highway to collapse.

Italian firefighters tweeted that they had sent rescue and emergency squads, including one from their urban search and rescue team.

Images released earlier by the fire service showed burning cars in an adjacent carpark.

One video filmed by a motorist circulating on Twitter shows the moment the tanker exploded, when a black plume of smoke is suddenly swept away by a powerful ball of flame that takes over the entire horizon.

A video published on Twitter by the fire service showed a huge column of black smoke billowing from the wreckage of the truck.

Images released earlier by the fire service showed burning cars in an adjacent carpark.

andrew.koubaridis@news.com.au