LITTLETON, Colo. (CBS4) – The reward for information about the murders of Nicholas Kunselman and Stephanie Hart-Grizzell increased to $100,000 on Sunday. It was 21 years ago on this date when the couple was found at a Subway near Columbine High School in Littleton.

Stephanie Hart-Grizzell and Nicholas Kunselman (credit: Metro Denver Crime Stoppers)

Kunselman, 15, worked there, and Hart-Grizzel, 16, waited for him to get off of work.

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A fellow employee later noticed the lights were still on just before 1 a.m. The teenagers’ bodies were found behind the counter inside the restaurant.

Investigators say both were shot by at least one unknown intruder.

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The Jefferson County Sheriff’s Office hopes the increased reward will help draw in tips.

Stephanie Hart-Grizzell and Nicholas Kunselman (credit: Metro Denver Crime Stoppers)

“With this significantly increased reward, people who haven’t come forward with their information will be much more likely to do so now. We are continuing our diligent work to bring justice to Nicholas and Stephanie” said Jefferson County Sheriff Jeff Shrader.

Stephanie Hart-Grizzell and Nicholas Kunselman (credit: Metro Denver Crime Stoppers)

The reward was increased to $12,000 on Feb. 14, 2020. The reward is made up of contributions from Metro Denver Crime Stoppers, Franchise World Headquarters, LLC, Subway stores and anonymous donors.

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If you have more information about these murders, you’re asked to call Metro Denver Crime Stoppers (720) 913-7867 or submit a tip online. Tipsters can remain anonymous.

Danielle Chavira