Dozens of people are reported to have been killed after a large section of motorway bridge collapsed onto houses in the northern port city of Genoa.
The Italian Ambulance has reported "dozens of dead", according to Italian news agency Adnkronos.
The local fire brigade said also victims were likely after the bridge collapsed at around 11:30am (9.30am GMT) during torrential rainfall.
The fire service said it was feared that cars that were on the motorway had plummeted when it suddenly gave way.
It was reported that up to 100 yards of the motorway had collapsed.
An witness told Sky Italia television he saw "eight or nine" vehicles on the bridge when it collapsed in what he said was an "apocalyptic scene".
Transport Minister Danilo Toninelli said in a tweet that he was "following with great apprehension what seems like an immense tragedy".
Fire fighters, police and ambulances are arriving in the area.
Italian television showed images of the collapsed bridge, which was built on the A10 toll motorway in the 1960s.
Restructuring work on the bridge was carried out in 2016.