An air quality alert for northeastern Minnesota due to smoke from wildfires was extended Friday to cover the entire state.

The updated statewide alert by the Minnesota Pollution Control Agency (MPCA) runs until 6 p.m. Monday. Officials say air quality is expected to worsen over the weekend, with the peak concentration of smoke expected Saturday morning and afternoon.

The statewide alert came as smoke from Canadian wildfires filtered into Minnesota, making the air unhealthy. The smoke contains fine particles that can harm respiratory and cardiovascular systems, the MPCA said.

The air quality across northern Minnesota is expected to be unhealthy for everyone. That area includes Brainerd, Bemidji, East Grand Forks, Moorhead, International Falls, Two Harbors, Hibbing, Ely, Duluth, Roseau and the Tribal Nations of Leech Lake, Red Lake, Grand Portage and Fond du Lac.

"The general public should limit prolonged or heavy exertion," the National Weather Service said.

Air quality in the rest of Minnesota is expected to be unhealthy for people in sensitive groups. Those with asthma or other breathing conditions, heart disease, high blood pressure and diabetes are advised to limit their time outdoors this weekend, as are children, the elderly and those who are pregnant.

Most of Wisconsin is also under air quality alerts, according to the state's Department of Natural Resources.

To help cut down on pollution, activities such as outdoor burning should be avoided, and driving and vehicle idling should be reduced as much as possible, the MPCA said.

Friday's air quality alert may need to be extended as additional waves of smoke are possible, the agency said.