MARTINEZ >> A woman died and a man was hospitalized with major injuries Monday following a crash on a freeway, the California Highway Patrol said.

The one-car wreck happened about 10:32 a.m. in the northbound direction of Interstate 680, just south of the Marina Vista Avenue exit, according to a statement from the agency. The crash ejected the woman, who died at the scene.

Authorities did not identify her immediately, pending notification of her relatives.

The wreck also left a white van overturned.

According to the CHP, the Dodge in which the two people rode veered off the right shoulder, returned to the road, then crashed into the concrete center divider. It then overturned.

The man sustained major injuries, and medics treated him at the scene before rushing him to a hospital in an ambulance.

The CHP said neither of the people in the car were wearing seatbelts. They have not determined whether drugs or alcohol were involved.

Only one lane on northbound I-680 remained open immediately after the crash. The CHP issued a Sig Alert for severe traffic that lasted into the afternoon.