Murder Suspect Left 'Smiley Face' Written In Blood on Victim's Walls Before Chilling Confession: Police

Smiley faces continued to pop up around the victim's apartment complex following the murder, before a Dexter-fan neighbor confessed, was detained, recanted, was released, and eventually arrested.

A Colorado man was arrested for allegedly murdering his neighbor last month, and now the disturbing details about the gruesome killing have been revealed.

On September 12, the Lone Tree Police Department announced the arrest of Troy Marcus Reynolds Jr., 34, in connection with the murder of Kathleen Mayo, 57, who was found dead at her unit at Aspect Apartments in Lone Tree on September 4.

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Reynolds was charged with first-degree murder, and also faces charges of burglary, animal cruelty, menacing, and tampering with physical evidence, per the police.

The announcement of Reynolds' arrest came after the Lone Tree Police Department had shared two previously posts on Facebook about the homicide, claiming there was "no known danger" to the public.

Earlier this week, a little over a month following Reynolds' arrest, CBS Colorado obtained the arrest warrant that revealed horrific details, along with Reynolds' alleged chilling confession.

According to the outlet, citing the warrant, Reynolds shared with investigations that he was a fan of the crime drama Dexter, which follows a serial killer. Per police, he was a self-described recluse. He claimed he would only interact with people on social media, even having his meals and groceries delivered to his home. Reynolds also said he spent the majority of his days playing violent video games, per CBS Colorado.

"I've never seen his face ... because I looked to see if I'd seen this person around," a tenant named Madisson told the outlet of Reynolds, who lives next door to the victim's unit. "They said it was suspicious, and that was all we got -- but that we were safe."

Reynolds reportedly lived upstairs from Mayo's unit.

According to police, per CBS Colorado, Mayo was last seen walking her dogs on August 24. However, her body wasn't discovered until September 4 when police responded to a welfare check.

The warrant detailed the crime scene, stating that Mayo had "two distinct lacerations" on her neck and her "left hand appeared to be possibly missing," CBS Colorado reported.

Police allegedly wrote that Mayo's bedroom door featured a symbol that was described as "a circle, with two distinct dots and a straight line under, similar to a 'smiley face' image. The symbol was confirmed to have been drawn with blood."

The documented also noted, per CBS Colorado, that another tenant in the apartment called police two days after the victim's body was found, claiming there were multiple drawings on the walls of the hallway and on Mayo's door.

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Madisson said she thought the drawings were blood, recalling to the outlet while showing a reporter the hallway, "There were way more, like, bigger spots ... and then, like, right here, there was a huge one."

Police also reportedly said in the warrant that they believed the smiley face symbols in the hallway matched the ones in Mayo's unit. According to CBS Colorado, investigators said they later concluded the substance used to draw the symbols in the apartment hall was possibly ketchup or barbecue sauce.

In the doc, police wrote, per the outlet, that the "unknown suspect returned to the crime" after the murder.

Three days after Mayo's body was discovered, Aspect residents were notified about the investigation via email, according to CBS Colorado.

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It was then, Reynolds reportedly confessed, with the warrant noting that he called 911 several times -- and allegedly admitted to police, "The 57-year-old (woman? That) was me. It's obvious."

CBS Colorado reported that Reynolds was taken into custody and interrogated, with police also searching his home, where they allegedly discovered a 9 mm gun, an autopsy saw, and 13 large knives.

The suspect allegedly told police he had been drinking when he called 911, and then claimed he had no involvement in Mayo's killing.

He was subsequently released, per CBS Colorado. Police said Reynolds then returned to the apartment property, where he was surveilled by investigators, according to the warrant, per the outlet.

The Lone Tree Police Department announced Mayo's murder was a homicide and confirmed her identity in a September 8 Facebook post, and encouraged the public to "come forward with any information."

The next day, Reynolds was arrested and taken into custody on an unrelated charge. At the time, he was allegedly asked about the autopsy saw police found in his apartment, with the suspect claiming he was a collector.

According to CBS Colorado, when Reynolds was asked if there was a particular reason why he purchased the saw, he laughed, and replied no.

Police publicly named Reynolds as the suspect on September 12, and his charges.

Lone Tree later addressed public safety concerns -- particularly why police claimed there was no danger despite the evidence and gruesome details -- in a statement, per CBS Colorado.

"Our officers were on scene every day -- talking with the property management, interviewing every resident, collecting video, and following up on leads to identify and arrest the person responsible," police chief Kirk Wilson stated. "I understand people want information as things unfold, but with an active homicide investigation, we simply can't share every detail without risking the case or the court process. At the end of the day, an arrest was made, and we believe we have the right person behind bars."

According to CBS Colorado, Reynolds is being held without bond, and is hearing is set for December.