A total of 18 people have died as a result of a period of extreme cold weather in New York City, its mayor has said. Since late January, the city has endured a cold snap, including 13 days of temperatures of 0C (32F) or below – one of the longest stretches of sub-zero weather New York has seen in six decades. Over the weekend, another person "lost their life on the streets of our city," Zohran Mamdani said on Monday, adding that "each life lost is a tragedy, and we will continue to hold their families in our thoughts". While...