Two people are dead and a three-year-old boy is in critical condition following a head-on collision south of Garryowen on I-90's frontage road.
Reports say the crash happened about 4:45 p.m. Friday.
Montana Highway Patrol Trooper Eric Winburn says a woman was driving south as she pulled out of her lane to pass a vehicle.
He says she tried but was unable to avoid colliding with a vehicle headed north.
The woman died at the scene, and the man driving the northbound car died after being taken to a hospital.
A child who was in the woman's car was ejected. Winburn says the child is in critical condition,.
No names were released.