The incident started Monday night in Des Moines with a report of a stolen car. Police then got reports of shots fired from a moving car that matched the description.
Officers tried to intercept but the car sped away. Less than a minute later, the fleeing car hit a mail truck and crashed into a fence and trees. The passenger, 16-year-old Emilio Estaban Garcia died a few hours later at the hospital, and Wednesday night, the 17-year-old driver, Jair Sanchez-Banos, also died.
Police say a gun was found in the wrecked car.