Two people sustained significant injuries after a crash in Iron County Monday evening.

Sgt. Nick Street with Utah Highway Patrol said the crash happened on northbound Interstate 15 at milepost 48 near Kanarraville.

The crash happened when a black Jeep Wrangler and a black Peterbuilt semi traveling north in the outside travel lane.

Troopers said the semi was traveling about 75 m.p.h and the Jeep was traveling significantly slower than the semi when the semi collided into the rear of the jeep.

Troopers said the semi driver didn’t realize how slow the jeep was driving.

Troopers are investigating the possibility that the Jeep may have been traveling slow on the shoulder and for an unknown reason merged in front of the semi.

The impact of the semi caused the Jeep to go off the shoulder and then roll, according to troopers.

Both the male driver and a female passenger in the Jeep required extrication and were flown from the scene to the hospital., according to troopers.

All persons involved in the crash were wearing seat belts.

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