Three people died and another person was injured in a one-vehicle crash late Saturday night southwest of Sisseton.

Names of the four people involved have not yet been released pending notification of family members.

Preliminary crash information indicates that a 2012 Chevrolet Impala was southbound on Roberts County Road 28 when it left the roadway and entered the west ditch. The vehicle struck an approach, went airborne, struck a wooden post, landed on the driver’s side and started on fire.

Three vehicle occupants, a 30-year-old female, and two males, ages unknown, were pronounced dead at the scene. A 29-year-old male occupant sustained serious non-life threatening injuries. He was transported by ambulance to the Sisseton hospital and later transported to a Fargo, N.D., hospital.

Who was the driver has not yet been determined. Seatbelt use is under investigation.

South Dakota’s Highway Patrol is investigating the crash. All information released so far is only preliminary.