CHICAGO (CBS) — An 18-year-old man was charged with felony drunk driving for a crash involving a Chicago Fire Department fire engine earlier this week in the West Pullman neighborhood, in which nine people were injured.

Tuesday evening, a fire engine crashed into the passenger’s side of a 1996 Nissan Maxima when the car pulled in front of it at the intersection of 128th Place and Halsted Street as firefighters were responding to an emergency call nearby.

Three children and two adults in the Nissan were hospitalized in serious to critical condition, according to the Fire Department. Four firefighters were hospitalized in good condition.

The driver of the car, 18-year-old Christopher Caston, of Dolton, was initially charged with misdemeanor DUI and cited for failure to yield to an emergency vehicle, driving without proof of insurance and failing to stop at a stop sign. But the DUI charge was upgraded to felony aggravated DUI on Thursday, police said.

Caston was scheduled for a bond hearing Thursday afternoon.

A witness who tried to help the victims after the crash said the driver told him he did not hear a siren.

“He said that he saw the lights coming into the intersection, but it was too late,” Alex Parker said. “He said he didn’t hear no siren.”

Parker said the truck gave a blast with its air horn as it collided with the car.

Fire Department spokesman Will Knight said the engine was responding to an emergency call.

Knight said whether the siren was in use will be one of the focuses of the investigation, but declined further comment on the details of the accident citing the possibility of lawsuits.

(The Sun-Times Media Wire contributed to this report.)

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