A 32-year-old Ballantine woman died Thursday after she ran off the left side of South 16th Road.
The Montana Highway Patrol said the unnamed woman hit a tree and was not wearing a safety belt.
She was taken to a local hospital where she was later pronounced dead from her injuries sustained in the crash, according to Malin Murray, MHP Communications Center Supervisor.
MHP crime scene investigators say weather was not a factor. The roadway was bare and dry but alcohol and speed are suspected.