CLOCKWISE (from above): An Afghan walks during a snow storm in Kabul. Officials hope that the country's largest airport will reopen after being closed due to heavy snowfall; a Siberian tiger licks its paw at the zoo in Bucharest. Zoo officials are taking special measures to protect animals from the weeklong cold snap, Eastern Europe’s worst in decades, which caused power outages, frozen water pipes and widespread closure of schools, nurseries, airports and bus routes; local residents walk on a road as snow falls in the hill town of Murree, some 58 km northeast from Islamabad; a train runs through snow covered railway tracks as cold weather affect much of Britain, in Croydon, south London.