View a timeline of the investigation into Kansas City Chiefs fans’ deaths.

(NewsNation) — The probe into the deaths of three Kansas City Chiefs fans discovered in their friend’s backyard “remains an ongoing death investigation,” according to a report citing police, as preliminary toxicology findings suggest the presence of drugs in their systems.

“The case remains an ongoing death investigation,” Alayna Gonzalez, a spokesperson for the Kansas City Police Department, told People in a statement. “Currently, there have been no additional details or reports of this case revealed to any media, nor are there any plans to at this time.”

The news comes only days after police in Kansas City received the preliminary toxicology report on the men’s deaths, and according to family sources, the men had drugs in their systems, including cocaine and fentanyl.

Family members of David Harrington, Clayton McGeeney and Ricky Johnson told NewsNation affiliate WDAF they learned that police received the toxicology report, and police confirmed they have been in contact with the families.

Police, from the outset, said they do not suspect foul play in the deaths and that it is not a homicide investigation.

Tony Kagay, the attorney for the family of McGeeney, says the toxicology report is “just the first step” in finding out what happened to the three men. Kagay prefaced his comments by saying he has not personally seen the report, which police have not officially released.

The three men had gathered in January in Northland, Kansas, to watch a football game at their friend’s house. It was days later, though, that their bodies were located in the residence’s backyard.

The homeowner, who has not been charged and has been cooperating with police, says the men froze to death — but family and friends told NewsNation affiliate WDAF that this is one of many details that doesn’t add up for them.

The men are believed to have been last seen alive by Jordan Willis, the man who lived at the home where the three bodies were found. He has since moved out and reportedly checked into rehab.

Since then, the families have questioned the initial steps police took and their relative silence in the weeks since the bodies were found.

Willis’ attorney, John Picerno, previously told NewsNation his client “did nothing wrong” and had no idea his friends were lying dead in his backyard.

Autopsies are still pending to determine the cause of death. That could take several more weeks, according to the medical examiner.