Deadly cold snap sweeps through U.S. Midwest

Meanwhile, schools and offices are also closing in the U.S. Midwest as an arctic cold snap sweeps over the region.
At least seven people have been killed in several states as a result of the deep freeze.
Midwestern Wisconsin, Michigan and Illinois, among others, have declared states of emergency.
Officials are warning of almost instant frostbite as temperatures are dropping to minus 50 degrees Celsius in some places.
Ice-cold winds are also being accompanied by heavy snow causing travel chaos.
Thousands of flights have been canceled along with dozens of train services -- most of them in and out of Chicago.