DENVER (CBS4) – Two Denver-area women are being held responsible for providing the dose of heroin that led to the death of a third woman.

Ariel Nicole Walker, 30, pleaded guilty last week in U.S. District Court in Denver to heroin distribution resulting in death. Kayla Pagano, 24, was charged with the same offense.

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According to a press release from the court, Walker’s plea agreement explained the development’s that led to the incident. Walker went to Civic Center Park in downtown Denver looking to obtain heroin. A woman identified only by the initials “E.N.” was also seeking to obtain the drug and approached Walker with that request.

Using E.N.’s car, Walker and E.N. drove to a gas station at 88th Avenue and Garrison Street in Westminster to meet Walker’s dealer, Pagano. Walker purchased heroin from Pagano, then sold some of that heroin to E.N., who injected it.

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E.N. passed out and ultimately died in the back seat of the car. Her body was found in alley in Denver.

The Denver Medical Examiner determined through toxicology that E.N. died as a result of toxic effects from the drug.

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The Denver Police Department investigated the death with the help of the Federal Bureau of Investigation.