DaShawn Watkins, 29, is facing murder charges in connection with the death of 14-year-old Pauly Likens.
On June 25, the Sharon Police Department received a report that Likens had been missing since June 22, a news release from the Mercer County Coroner states.
That same day, the Hermitage Police Department was dispatched to a nearby lake, where they found dismembered human remains recovered in and around the water, officials stated. Likens' remains were recovered in the area surrounding Shenango River Lake over the following week, according to state police.
An autopsy revealed that the cause of death was ruled to be a sharp force trauma to the head, and the manner of death was ruled a homicide.
Surveillance footage, social media records and cellular phone records found that Likens appeared "to be on the phone and waiting to meet someone near the canoe launch area," state police said.
Officials say footage also captured Watkins making several trips out of his apartment carrying multiple bags, and driving to his apartment in the vehicle seen near the crime scene.
Multiple locations in Watkins' apartment tested positive in a preliminary blood test, according to the Pennsylvania State Police.
He has been charged with first-degree murder, aggravated assault, evidence tampering and abuse of corpse after allegedly murdering and dismembering Likens.
"Pauly would have been 15 years old this past Saturday, and instead of celebrating their birthday, mom's still trying to figure out how to plan a funeral," said Pamela Ladner, president of the LGBTQIA+ Alliance Shenango Valley. "We're very far from where we thought we were and where we need to go as far as advocacy and keeping our youth safe, especially the LGBTQ youth in particular."
Ladner, who is speaking on behalf of the victim's family, told ABC News that Likens was a jokester who played pranks on her family and was a selfless and loving kid.
The victim's family and LGBTQ activists say the killing was a hate crime, but those charges have not been brought yet.
Watkins' next preliminary hearing will be on July 17 and another is scheduled for July 25. His arraignment was on July 3 and he was denied bail. He has not yet entered a plea.
A candlelight vigil for the teen is being planned for July 13 by local LGBTQ activist groups.
ABC News contributed to this report.