December 9, 2024: UnitedHealthcare CEO Brian Thompson shooting suspect Luigi Mangione charged with murder

Detectives investigating the killing of UnitedHealthcare’s chief executive have recovered possible DNA evidence from items found at the scene and have now turned it over to a lab for testing, according to a senior law enforcement official briefed on the investigation.

However, a partial fingerprint and DNA have so far not yielded matches when compared against respective law enforcement databases, according to a law enforcement official on Monday.

Police are testing a fingerprint recovered from a purported burner phone thought to have belonged to the suspect and DNA recovered from a water bottle and energy bar wrapper he is said to have bought — but so far neither have turned up any matches.

The official told CNN that NYPD investigators finished processing the items and turned the samples over to the Office of the Chief Medical Examiner for testing Friday.

Why this matters: The various pieces of evidence being uncovered by police are crucial not only for finding the gunman — but also for his prosecution.

“The DNA evidence is important. Everything is for courtroom testimony so we can link him to the crime,” retired NYPD Detective Michael Alcazar told CNN on Friday.

In addition to the water bottle and the cell phone, investigators also have a trail of surveillance video sightings as well as ammunition with the words “delay,” “deny” and “depose” written on them left at the scene of the crime, sources told CNN. The NYPD also released new images of the person of interest without a mask at the hostel where they believe he was staying at before the shooting.

“Our DNA, our fingerprints are left everywhere — It could be on the countertop of that hostel, so as prepared as you think you might be, there’s mistakes that people make all the time and law enforcement relies on that,” Alcazar said.