mark duggan was shot in england in 2011 by police officers who said he was armed and dangerous. his death sparked rioting over the next four days. and arctic air hit the united states today. there are some signs the condition might be easing. the polar vortex has led to frigid conditions. even hell has frozen over, the city in michigan. we have the report. >> the road to hell. has become anmlet andy expanse of snow, wind, subzero conditions. it might look nice, but it doesn't feel so good. cold.atures are at around 12 degrees fahrenheit, that is -11 degrees celsius. a few hours ago, it was even colder. this town was covered in a blanket of snow. hell had quite literally frozen over. there was hardly anyone willing to brave this weather. john runs the ice cream shop. >> the temperature when we hit 19 degrees below zero, the chill -40, it has been a while since anything like that has happened. forecasters in the u.s. blaming this cold spell on what is known as a polar vortex. severe gusts of arctic winds, which brings frighteningly cold temperatures. business has dried up, but the