Italy is facing a major pollution crisis after a cargo ship carrying tens of thousands of tonnes of fuel sank of the northern coast. Thirteen crew members were winched to safety from the vessel, the Margaret, after it ran onto rocks in the harbour at La Spezia in bad weather. It was heading from Genoa to the Bulgarian port of Varna.Italian authorities have declared a pollution alert as efforts continue to contain the spill. Two specially adapted craft have been sent to the area to prevent the slick reaching land. The extreme conditions have caused other problems in Italy. Heavy snowfalls blocked roads in the north of the country. Hundreds of people travelling on a motorway between Milan and Genoa were stranded in their cars for a time. In Venice it was rain that created the difficulties. More than a third of the historic lagoon city, including Saint Mark’s square, was flooded after lengthy downpours.