ADAMS COUNTY, Colo. (CBS4) – A 38-year-old Adams County man who allegedly confessed to murdering his friend and encasing his body in concrete is now facing formal criminal charges of first-degree murder after deliberation and tampering with a deceased human body. Authorities say Russell Montoya Jr. shot and killed Shane Nelson, 38, during a fight on Nov. 8 at his apartment on the 7800 block of York Street in unincorporated Adams County near the Thornton city limits. Several days later Adams County Sheriff’s deputies found Nelson’s body encased in concrete in the apartment’s basement.

Shane Nelson

Shane Nelson (credit: GoFundMe)

A judge formally advised Montoya of the charges he faces in Adams County District Court on Thursday. A preliminary hearing has been scheduled for Dec. 10.

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According to court documents, Montoya’s daughter turned her father in. She told investigators that Nelson, a friend of her father’s for about 25 years, came over to their home on the night he was killed. She left home that night and when she returned the next morning, she told police her father was “sweaty and acting very nervous” and asked if she needed to go to her room in the basement.

Russell Montoya Jr.

Russell Montoya Jr. (credit: Adams County Sheriff)

When she walked down the stairs into the basement she told investigators she was met with an overpowering “horrible” and indescribable odor. According to the affidavit, she described smelling bleach, vomit and burnt hair along with a strong chemical odor. The daughter also observed a reddish-brown stain in the carpet on the center of every step leading into the basement.

When the daughter texted her father asking about the stain, he said there was a fight and someone threw up on the stairs.

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A few days later the daughter noticed a missing persons report for Nelson on social media and asked her dad about it. He responded that he shared the post and hoped Nelson was okay.

Investigators said the daughter noticed that the concrete in the basement laundry room appeared to be freshly poured. When the daughter confronted Montoya about her suspicions on the phone, she told police he confessed that he and Nelson got in a fight and Nelson reached for a pistol tucked in Montoya’s waistband. That’s when Montoya told his daughter that he drew the pistol and shot Nelson in the kitchen.

Shane Nelson

Shane Nelson (credit: GoFundMe)

According to the affidavit, Montoya told his daughter he and his wife spent 12 hours cleaning up the blood before he buried Nelson in concrete in the basement. Montoya told his daughter he had no intention of leaving the house and was going to “keep Shane company.” When asked what he would do if she called the police, Montoya told his daughter he would not go to prison and would “shoot it out” with the cops.

Investigators and emergency crews outside Russell Montoya Jr.'s home in unincorporated Adams County.

Investigators and emergency crews outside Russell Montoya Jr.’s home in unincorporated Adams County. (credit: CBS)

The Adams County Sheriff’s Office SWAT team executed a search warrant of the home late on Nov. 14 and took Montoya into custody. In an interview with investigators, Montoya allegedly said he made the decision to to keep Nelson’s body in the home and make him a “tomb” in the laundry room. He also told investigators he believed it was self defense when he shot Nelson because he reached for his gun.

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Investigators carry Shane Nelson's body onto a stretcher from Montoya's home.

Investigators carry Shane Nelson’s body onto a stretcher from Montoya’s home. (credit: CBS)

So far, Montoya’s wife doesn’t face any charges in the case.