PLATTSMOUTH, Neb. (AP) — Authorities are investigating a collision that killed one person and critically injured three others in southeast Nebraska.

The crash happened around 10 a.m. Sunday on U.S. Highway 75 south of Plattsmouth.

Officials say two vehicles collided nearly head-on. Both vehicles had two occupants.

One person died at the scene of the crash. Two were flown to hospitals by helicopter, and one was taken by ambulance.

None of the victims were immediately identified, and officials didn’t say what caused the crash.