The state Pollution Control Agency has issued an air quality alert for the western portions of northern and central Minnesota through 9 am Saturday due to wildfire smoke drifting south from Ontario. Officials say the smoke arrives this afternoon into early evening from Bemidji to Moorhead, and during the late evening and overnight from Alexandria to Saint Cloud. People with lung or heart conditions are more likely to be affected when fine particle pollution reaches an unhealthy level — but officials say everyone should limit their physical activity.