The US is home to some of the most polluted air on the planet as smoke from 120 out-of-control Canadian wildfires drifts across the border.

Wildfires in Canada are pouring thick clouds of smoke into the US and will usher in unhealthy air quality for millions of people in Northeast and Midwest.

Wildfires in Canada are pouring thick clouds of smoke into the US and will usher in unhealthy air quality for millions of people in Northeast and Midwest.

A massive plume of smoke from wildfires burning across Canada has swept into the United States, degrading air quality across the Midwest, Northeast and Mid-Atlantic.

The wildfires are burning in Ontario, Canada, Minnesota, and nearby regions, with smoke already affecting cities in the Midwest.