Extreme cold in US north-east closes schools and Covid testing sites

Massachusetts, New York and Maine brace for sub-zero temperatures with wind chill factor, increasing risk of frostbite

A mass of Arctic air swept into the US north-east on Tuesday, bringing bone-chilling sub-zero temperatures and closing schools for the second time in less than a week.

Schools in Massachusetts' three largest cities, Boston, Worcester and Springfield, canceled classes, saying they did not want children standing outside for extended periods of time waiting for buses.