MCHENRY COUNTY, Ill. (WGN) — A wrong-way crash killed a mother, her four children, and two others Sunday on an interstate in northern Illinois.

The woman’s husband was seriously injured.

The crash occurred around 2 a.m. Sunday on I-90 in McHenry County, roughly 50 miles from Chicago.

Illinois State Police say 32-year-old Thomas Dobosz and his 31-year-old wife, Lauren Dobosz, both from Rolling Meadows, were driving westbound on I-90 near Hampshire in a full-size Chevrolet van carrying five children.

According to police, 22-year-old Jennifer Fernandez, of Carpentersville, was driving in the wrong direction on the highway “for unknown reasons” and collided head-on with the van. Both vehicles became engulfed in flames.

Thomas Dobosz was the sole survivor of the crash and suffered serious injuries. Lauren Dobosz and the children — ages 5 to 13 — were killed.

A neighbor who lives across the street from the couple said they had four children. He believes the fifth child involved in the crash was a friend of their oldest child.

Fernandez also died, police said.

Authorities temporarily closed the interstate’s westbound lanes near the crash but reopened the highway later on Sunday morning.

Police say the crash investigation is ongoing.