DENVER (CBS4)– Denver police are investigating the operation of a system that is supposed to change stoplights when an emergency vehicle approaches. One person was killed Saturday and two others injured when a fire vehicle collided with a Honda Civic in the middle of a busy intersection.

(credit: CBS)

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The question is, why were the fire rescue vehicle and the Honda Civic in the same spot at the same time?

Britney Garcia was driving south on Broadway when the Honda passed her.

“He was on the right of me and he went around the truck and then he tried to speed. He tried to beat the fire truck,” she told CBS4 investigator Rick Sallinger.

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Denver uses what’s called an Opticom system where an approaching emergency vehicle sends out a signal to a receiver on the stoplight to turn it green. It also turns the light red for crossing traffic.

Denver Fire Chief Desmond said Sunday, “We have Opticom at some intersections and DPD is looking into the working ability of the Opticoms in this particular incident.”

(credit: CBS)

The fire truck was headed northwest on Speer to a call. The Honda was going south on Broadway. The lights are supposed to change 1,000 to 3,000 feet before reaching the intersection, according to Denver Fire Captain Greg Pixley.

Garcia said the stoplight appeared to change after that, “It was green when I heard the fire trucks, but when the fire truck was in the middle of the intersection where the lights are, it turned red.”

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The Denver Fire Rescue One vehicle had T-boned the sedan, killing the adult female driver and critically injuring two others inside. Pixley said computer data and any video that turns up should be able to determine if the Opticom system for changing the stoplights was working properly.

Rick Sallinger