Authorities say a 4-week-old baby died of injuries sustained in a single-car crash in Hackensack Saturday night.

The Bergen County Prosecutor's Office says it happened around 9:30 p.m. The Hackensack Police Department received a 911 call about a vehicle that had crashed into a pole on Passaic Street.

A Hackensack couple and their baby boy were inside the vehicle. The baby suffered head trauma from the crash and was later pronounced dead at Hackensack University Medical Center, according to the prosecutor's office.

The cause of the crash is under investigation by the Bergen County Prosecutor's Office Fatal Accident Investigation Unit and the Hackensack Police Department.

The occupants of the vehicle have not been identified at this time, and further information has not been released.