Spain is in a race against time to clear roads covered by heavy snow, and get Covid vaccines and food supplies to areas affected by Storm Filomena. Up to 50cm (20 inches) of snow fell on the capital Madrid, one of the worst hit areas, between Friday and Saturday. At least four people died and thousands of travellers were left stranded. Overnight, temperatures plunged to -8C (18F) in parts of Spain, amid warnings by meteorologists that the snow was turning to perilous ice. The unusual cold wave on the Iberian peninsula is expected to last until Thursday. The Spanish government said it had taken extra steps - including police-escorted convoys - to ensure its expected shipment of some 300,000 coronavirus vaccines can be distributed as planned to regional health authorities later on Monday. "The commitment is to guarantee the supply of health, vaccines and food. Corridors have been opened to deliver the goods," Transport Minister Jose Luis Abalos said on Sunday. Soldiers have been deployed to clear some of the 700 major roads. Some 3,500 tonnes of salt were later brought on lorries to the capital, Spain's El Mundo website reported on Monday. The record-breaking snowfall has triggered some unprecedented scenes here in Madrid. People have skied along the city's main commercial street, Gran Vía, and one man was pictured being pulled through the district of Hortaleza on a sled by five huskies. But other responses to the snow have been more controversial due to concerns about Covid-19. Dozens of young people had a snowball fight in Callao square, for example, and many of them were without facemasks. Nearby, in Puerta del Sol, others celebrated the snow by dancing a conga. The daily Marca newspaper branded it "the conga of shame". Although the snowfall has now stopped, low temperatures have left snow and ice piled up across the capital and the surrounding region. And with residents advised to avoid using their cars, public transport has seen a surge in demand. This has compounded coronavirus concerns as many metro train carriages were packed at rush hour on Monday morning, making social distancing impossible.