Rep. Calvin Callahan joined lawmakers from Iowa, Minnesota and North Dakota in filing a formal complaint against Canada over wildfire smoke.

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.

Smoke from Canadian wildfires has drifted thousands of miles across the U.S., remaining suspended in the atmosphere for days, according to CNY Central. Meteorologist Violet Scibior explains that intense heat pushes smoke up to 5 miles high into the jet stream,

Smoke from fires across the West and Canada is causing potential health risks for people across the U.S. Satellite images show smoke from the wildfires in California is creating unhealthy air as far away as Las Vegas.