PHOENIX -- Investigators are working to determine the cause of a crash between a fire truck and pickup that killed a young couple and their infant son.
The crash happened at a Phoenix intersection on Sunday morning.
Police say the pickup driver, 20-year-old Kenneth Collins, was pronounced dead at the scene. His 3-month old son, also named Kenneth, and the baby's mother, 19-year-old Dariana Serrano, were both pronounced dead at a hospital.
They say the fire truck was responding to an emergency call at the time of the crash and had its lights and sirens on.
Investigators say Collins made a left turn in front of the oncoming fire engine.
Police say the three firefighters on board are recovering from their injuries.