Police investigating 'suspicious' death of person looking into young Florida mother's 2010 death Police say this private citizen was conducting their own personal investigation.

Florida police are investigating what they are calling a "suspicious" death of a private citizen who was conducting their own personal investigation into the 2010 death of young Florida mother Michelle O'Connell.

The victim was found shot dead at a condo in the World Golf Village in St. Augustine, Florida, Thursday morning, according to the Putnam County Sheriff's Office. Police have not released the victim's name, but said the victim identified as both male and female.

Police also said this person had requested to view some public records related to the O'Connell case, but what they were actually able to see was unknown.

O'Connell's mother Patty O’Connell told ABC News Thursday that she was devastated by the news of the victim's death.

The Putnam County Sheriff's Office said it took over the investigation into the "suspicious" death Thursday afternoon from St. Johns County Sheriff's Office due to its department's involvement in the O'Connell case.

"20/20" first profiled O'Connell's case last year. On Sept. 2, 2010, O’Connell, 24, was found lying on the bedroom floor of her boyfriend, St. Johns County Sheriff’s deputy Jeremy Banks', St. Augustine home with a gunshot wound to her head. The gunshot had come from his service weapon and Banks had called 911, according to police. O'Connell was pronounced dead later that night.

Her death was officially ruled a suicide but her family has long believed it was a homicide.

Banks has always denied hurting O'Connell the night of her death and he has never been charged with a crime. He remains a sheriff’s deputy with the St. Johns County office.

Putnam County Sheriff's Office said they have not questioned Banks about the private citizen's death.

To this day, the O’Connell family has refused to believe that O’Connell, who at the time had a 4-year-old daughter and had just landed her dream job at a day care center, would take her own life.

Over the years, the family has fought to have her case re-examined, including petitioning then-Florida Gov. Rick Scott last year to assign a new prosecutor to her case, and even had O'Connell's body exhumed for a forensic pathologist to conduct a second autopsy.

“You can't grieve until you get justice," Patty O’Connell told ABC News in an interview last year. “You have to have your justice. And it never goes away.”

The St. Johns County Sheriff's Office told "20/20" in a statement last year that "this case has been extensively reviewed by numerous investigations" which "have continually ruled the death a suicide."