An infant has died from injuries he received during a two-vehicle crash in Alabama that involved an ambulance, police said.

Four-month-old Israel Barrera was critically injured in the wreck on Tuesday afternoon in Montgomery, Police Capt. Saba Coleman told the Montgomery Advertiser. He died at a hospital.

The ambulance and a Nissan Altima — in which the baby was a passenger — collided. Police say the cause is still under investigation.

There wasn’t a patient in the ambulance at the time of the crash, according to Coleman. The two emergency medical service workers inside received minor injuries.

The driver of the Altima and another passenger received injuries that weren’t life-threatening.