The scene of the accident stretched for about four kilometres (2.5 miles)

Cars and lorries crashed into each other in thick fog along a motorway between the cities of Venice and Trieste, in what the police said was one of Italy's worst road accidents.

"They were driving too fast in the conditions," highway police official Pietro Luigi Saga was quoted as saying by the Associated Press news agency.

Mr Saga said that 15 of the injured were in critical condition.

The scene of the accident stretched for about four kilometres (2.5 miles) along the highway, as firefighters rushed to rescue drivers.

Italian television showed cranes and tow lorries trying to clear the scene and pull mangled cars away.

Second pile-up

Mr Saga said that the pile-up was caused by the collision of two lorries heading from Venice to Treviso early on Thursday on the A4 motorway in Cessalto, near Trieste.

Firefighters rushed to the scene to rescue trapped drivers

He said that other vehicles in the same lane crashed into the two lorries which stopped in the middle of the motorway.

Mr Saga said that in the opposite lane drivers stopped to look at the crash, causing a second pile-up.

He said that among the vehicles in the crash was a school bus, and that one injured child was taken to hospital.