AURORA, Colo. (CBS4) – A man witnessed his wife get killed on Wednesday night when she was struck by a pickup truck while riding her bicycle.

Police say a woman driving a truck ran a red light and hit Denise Pimple, 57, who was biking with her husband.

The crash happened at 6:40 p.m. at East Yale Avenue and South Ursula Street.

Police say the man and his wife had the right of way, and it appears they did not see the pickup coming towards them. They had pressed the button to get a walk signal, and the victim was wearing a helmet.

Drivers nearby also tried to stop the woman who was driving.

“Two other cars — the one that was stopped there and the one that was behind the pickup — were seeing what has happening and honking their horns trying to alerting the driver of the pickup truck,” said Aurora police Lt. Jeff Turner. “There’s no indication that the bicyclists knew anything was coming.”

The man on the bike was not hurt. Pimple was pronounced dead at the hospital.

Officers said they were investigating whether the woman driving the pickup had drugs or alcohol in her system. They said sun glare may have also played a role in the incident.

Aurora police Lt. Jeff Turner said the driver will likely face charges for running the light and possibly more serious charges depending on the outcome of toxicology tests, which could take a month to complete.

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