GRAND ISLAND, Neb. (AP) — Authorities are trying to determine what caused a minivan to veer off Interstate-80 in central Nebraska this weekend and kill two people.

A mother was travelling with two teenagers when the crash happened near the Wood River exit on Saturday afternoon. The 47-year-old woman and a teen girl died.

The Hall County Sheriff’s department says a 17-year-old boy was taken to a Grand Island hospital for treatment after the wreck.

The sheriff’s department says the 2005 Dodge Caravan swerved off the road and rolled several times in a ditch on the north side of the interstate.

Authorities didn’t immediately identify the people involved in the crash.