GRAND RAPIDS, Minn. (AP) -

A 72-year-old woman is in critical condition after a backyard fire at a farm in northern Minnesota.

The Itasca County sheriff's office says Patricia Pauna suffered severe burns on her legs and arms when she tried to put out the grass fire with a shovel Tuesday.

Pauna was airlifted to Essentia Health St. Mary's Duluth Hospital burn unit. She was in critical condition Wednesday.

Authorities say the fire started from a burning pit in the backyard and spread to tall grass and outbuildings. The fire was contained soon after firefighters arrived.