JEFFERSON CITY, Mo. (AP) — A Columbia man has pleaded guilty to participating in a conspiracy to distribute synthetic heroin, which resulted in the death of another man.

Nick Connor Burris pleaded guilty Thursday in federal court. Co-defendant Marquette Deandre Murrell, of Columbia, pleaded guilty to the same charge in December.

Columbia police say Burris admitted he supplied the drug to an 18-year-old man who was found dead of a drug overdose in August 2015. He admitted he bought the drug from Murrell, who told him it was 95 percent pure and should be diluted. Burris mixed the synthetic heroin with Benadryl before giving it to the victim, whose name was not released.

Burris and Murrell each face up to 20 years in federal prison without parole, plus a fine up to $1 million.