At least 15 people have been killed and some 50 injured after a freight train carrying gas derailed and exploded in northern Italy, officials say.
The wagons jumped the tracks and crashed into several homes, setting off an inferno in the seaside town of Viareggio in the middle of the night.
Several of the victims died when their houses collapsed. There are fears some people may be trapped under the rubble.
Officials say there is still a risk that other gas tanks could explode.
The explosion happened shortly before midnight local time on Monday when one wagon in the 14-car train carrying liquefied petroleum gas came off the tracks before ploughing into several homes near the station in Viareggio.
A number of fires immediately broke out in the area.
Several of the victims, including at least one child, died when their houses collapsed with the force of the blast.
At least two other people are thought to have been killed on the road next to the station. Many of the injured suffered severe burns.
About 1,000 people were evacuated from the area.
Police say the incident may have been caused by damage to the tracks or a problem with the train's braking system.
The train's two engineers, who were only slightly injured, said they felt an impact about 200m outside the station, shortly before the rear of the train derailed, officials say.
Liquefied petroleum gas is a mixture of propane and butane that is used for cooking or as fuel for specially-adapted vehicles.