Watch: huge and deadly fireball engulfs Italian highway after tanker crash in Bologna

At least one person was killed and more than 60 others injured Monday when a tanker truck crashed into a truck and exploded, sending a fireball across a busy motorway in the northern Italian city of Bologna.

The blast, which occurred in the early afternoon in the Borgo Panigale area, close to Bologna airport, caused a partial collapse of the flyover, where the explosion took place, onto another road below, filling the scene with flames and black smoke.

A video released by the police shows the moment the tanker ploughed into the back of the truck, immediately catching fire as another truck crashed into the back of the blazing tanker, and oncoming traffic screeched to a halt.

The three vehicles, covered by the blanketing smoke, were reduced to little more than ash by a massive explosion that swept across the motorway and could be heard throughout the city.

“I was here (at a nearby restaurant) for work … at a certain point we heard a violent blast, I thought it was a terrorist attack,” Marco Rosadini, whose car is trapped under the flyover, told the daily La Repubblica.

“After the explosion the roof of the restaurant started to collapse. I looked outside and I felt like I was looking at a wall of fire.”

It took firefighters nearly two hours to extinguish the fireball, which spread to vehicles parked in a nearby lot of a car dealership.

Then rescuers began the delicate task of looking through the burned out debris to find any victims.