Police in Colorado are searching for the cause of death of 5 adults found deceased in an apartment.

According to a press release from the Commerce City Police Department, on Sunday, February 20, officers were dispatched to an address in the 14400 block of E. 104th Avenue based on a report of several adults who were unconscious.

North Range Apartments | Commerce City, Colorado

When authorities arrived on the scene, they discovered 5 deceased individuals, 3 females, and 2 males,  who were initially believed to be unconscious by the emergency caller.

The female individual who made the emergency call was the only surviving adult, but there was also a four-month-old infant that was on the scene.

Potential Party Gone Wrong | Commerce City, Colorado

A neighbor by the name of Ian Scott, 31, told the Denver Post that a party had occurred the night before. Scott reported hearing loud music on Saturday evening and on Sunday afternoon saw the surviving female looking distraught on the phone outside with the baby.

Authorities did not find any evidence of blunt trauma or violence.

However, police did find an unknown substance which they believe may have been "illicit narcotics laced with fentanyl."

In a news conference, Police Chief Clint Nichols had this to say about the fatal incident:

“If it is going to be illicit drugs, they were very, very bad,” he also stated, "it happened pretty quickly — speculation on my part."

What Happened at North Range Apartments? | Commerce City, Colorado

The baby was taken to the hospital and is said to be okay. Reports have not revealed whether the infant is a girl or boy, or if the infant's parents may have been one of the victims.

The fire department is also said to have tested the apartment for hazardous gases and received negative results.

There are still several questions that have been left unanswered, but the investigation is ongoing.

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