One person is dead and another has life-threatening injuries from a one-vehicle crash on Interstate 90 west of Humboldt.
The South Dakota Department of Public Safety says a 1999 Ford Ranger was headed east on I-90 when the driver lost control. The vehicle left the road and rolled before coming to rest in the westbound lanes of the interstate. Both people in the vehicle were ejected. The passenger died at the scene; the driver was taken to the hospital.
Authorities say speed and slippery road conditions contributed to the crash.
The names of the people involved will be released once family is notified.