Air quality has taken a serious hit across the United States as a twofold blow of wildfires in the West and in Canada have sent smoke pouring across large sections of the country — a problem that’s set to linger for days.

At least three people have been injured and hundreds of homes and businesses are at risk in California as a massive wildfire spreads across the Los Padres National Forest. Smoke blowing over Las Vegas from the California wildfire created a hazy sky and poor air quality over Sin City Monday.

A stretch of northern Ontario remains under a special air quality statement amid smoke from wildfires burning in parts of the country.