A man has been charged with the murder of the witness of a homicide, which he is also suspected of committing, in Denver, Colorado.
Steven Young, 45, was charged with murder in the first degree and possession of a weapon by a previous offender by the Denver District Attorney Beth McCann on Wednesday for the June killing of Charly Lewis.
Lewis, 32, was found dead in an alleyway by a cyclist on June 7 around 5 a.m., according to a public arrest affidavit.
When officers arrived on the scene, they discovered Lewis' body "slumped against the fence with a hooded sweatshirt pulled up tight to her chin and around her head. Officers observed blood running down from underneath the female's head and neck area." Paramedics who arrived ahead of police said that she was first found facedown, according to the affidavit.
A spent .40 caliber shell casing was found by officers on the ground near Lewis' foot. An intact bullet was found underneath her head.
Denver District Attorney's Office Steven Young
Investigators discovered that officers in Aurora, Colorado, had been attempting to contact Lewis because she was a witness to a murder there just days earlier.
Young was listed as the suspect in that homicide and had an outstanding warrant for murder in the first degree that was issued on June 4. Aurora police had contacted Young on June 1 while he was in a car with Lewis, the affidavit says.
Investigators "learned that a witness had identified Charly Lewis as the person who was present with Young during the murder and that Ms. Lewis had witnessed Young commit the murder in Aurora," the affidavit says. Aurora detectives told Denver police that "one of the reasons the Attempt to Locate was issued for Lewis was because they were in fear for her safety" if she was a witness to the homicide.
On June 8, Aurora police had arrested Young in connection to the homicide — one day after Lewis was found dead.
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Lewis and a man who appeared to be Young were seen walking together on surveillance footage in the area the night Lewis was shot, the affidavit says.
According to the affidavit, investigators "observed other surveillance videos from around the area where the victim was found dead," and "observed the black male and the victim walking together on numerous occasions throughout the early morning hours, including seeing the two of them on the same surveillance camera" at the location Lewis was killed.
An autopsy conducted on June 8 revealed that Lewis had been shot in the back of the head, and the medical examiner ruled her death a homicide, according to the DA's office.
It was not immediately clear if Young has legal representation or has entered a plea at this time. He is scheduled to appear in court on October 30.
The Denver Police Department did not immediately respond to PEOPLE's request for comment.