Emergency personnel responded just before 6 p.m. Saturday to a single-vehicle crash on I-255 eastbound near the Columbia exit. A white Jeep SUV went off the roadway and struck a guardrail.
Responding agencies included Columbia police, fire and EMS.
Illinois State Police said the driver, Amy McGuire, 41, of Columbia, said her cell phone had fallen from its dash mount and as she reached to pick it up, her vehicle ran off the road to the right. The vehicle struck a previously damaged guardrail.
McGuire was transported by ambulance to an area hospital for treatment of life-threatening injuries, ISP said.