At least 14 of the injuries were considered serious, local news site ANSA reported.
Police closed off the road where the crash took place as well as the surrounding area of Borgo Panigale, on the outskirts of the city of Bologna. Videos show flames shooting up in the air after the explosion, replaced later by a thick black cloud of smoke.
He said that there were seven to eight minutes of what sounded like explosions causing the glass roof of the restaurant to collapse.
Katherine Lam is a breaking and trending news digital producer for Fox News.
Fire raging on the motorway outside Bologna
It also shut down a highway north of the city that is a key route between northern Italy and the Adriatic Coast and other points south, including Florence and Rome, the capital.
Residents living on the other side of Bologna said they heard the blast.
They wrote: "tanker explosion: extinguished the flames, in progress the cooling operations".
Italian police told the ANSA news agency on August 6 that 14 people were seriously injured in the explosion, which was caused by a vehicle carrying flammable materials.
Video of the incident showed the tanker truck, which contained inflammable materials, slamming into the back of a lorry which had come to a halt because of heavy traffic.More news: 'Starving' children are found on United States compound
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