MINNEAPOLIS (AP) — The Minnesota Pollution Control Agency has extended an air quality alert until noon on Tuesday for the entire state due to what authorities are calling an “unprecedented significant air quality event.”

Minnesota has been dealing with smoke from Canadian wildfires that has created some of the highest particulate readings on record. An air quality alert was set to expire Friday afternoon, but it was extended.

The MPCA says fine particle levels are expected to reach a level that’s considered very unhealthy for everyone, across north central and south central Minnesota.