BILLINGS, Mont. (AP) — A Harrison woman died and five children were injured in a head-on collision in southeastern Montana.

The Montana Highway Patrol says the 39-year-old woman was westbound on U.S. Highway 212 between Crow Agency and Busby at about 5:20 a.m. Tuesday when for an unknown reason her sport utility vehicle drifted into the oncoming lane of traffic and collided with an eastbound pickup truck.

Trooper Justin Kirchheck tells The Billings Gazette the vehicles collided driver's side-to-driver's side.

The woman died at the scene. Her name has not been released.

Her children, ranging in age from 16 months to 18 years, were taken to a Billings hospital for treatment of their injuries.

The driver of the pickup wasn't injured.