The causes of death have been revealed for the three Kansas City Chiefs fans who were found dead in the backyard of their friend’s home in January 2024.

A forensic exam determined David Harrington, 37, Clayton McGeeney, 36, and Ricky Johnson, 38, “all died of fentanyl and cocaine combined toxicity,” according to court documents reviewed by Fox News Digital.

The documents reveal what responding officers encountered the day they were called to the Kansas City, Missouri, rental home, where the group of longtime friends had celebrated the Chiefs’ victory just days earlier.

On Wednesday, Jordan Willis and Ivory J. Carson were charged with three counts of involuntary manslaughter and two counts of delivery of a controlled substance except 35 grams or less of marijuana or synthetic cannabinoid. Each charge carries a maximum of 10 years.

On Wednesday, Jordan Willis, left, and Ivory J. Carson were charged with three counts of involuntary manslaughter and two counts of delivery of a controlled substance except 35 grams or less of marijuana or synthetic cannabinoid. Each charge carries a maximum of 10 years. (Platte County, Missouri Sheriff’s Office)

Two other unidentified witnesses, who were present at the football watch party, told police that they “drank, smoked marijuana and used cocaine.” One of the witnesses said that he left “shortly before midnight” on Jan. 8, documents said. 

Another witness said that before heading to Willis’ rental home, he saw a “large plate of cocaine allegedly supplied by Mr. Willis that everyone was using” at Harrington’s home, the documents said.

Court records also indicated that Carson, who went by “Blade Brown,” supplied and sold cocaine to Willis and the victims, and that his DNA was found on a bag of fentanyl.

The Kansas City Police Department said that it investigated the three deaths for 14 months before charges were filed.

“KCPD detectives never stopped working on the case, waiting for all the facts to come in. Reaching this point is a testament to their dedication to delivering justice for the victims and their loved ones,” Kansas City Police Chief Stacey Graves said Wednesday.

Fox News’ Stepheny Price contributed to this report.