At least ten people are dead and dozens injured after a rail derailment sparked a massive explosion in north-west Italy.The accident happened in the Tuscan coastal town of Viareggio. A freight train travelling from La Spezia to Pisa, and made up of wagons carrying gas, had just passed through Viareggio station when the derailment happened. Houses nearby caught the full force of the exploding freight cars and were reduced to rubble. Survivors were rushed to nearby hospitals in Viareggio – at least 20 people have serious injuries. The search is on for more victims. Five of the dead were trapped under tons of masonry. One man was riding a scooter near the railway when he died. Rescuers have evacuated the area for fear of more explosions. This is one of the worst rail accidents in Italy in recent years. A probe is underway to find out what caused the derailment, including whether the freight train collided with another.