Investigators in Washington County, Minnesota, say they've identified the human remains found in two Twin Cities lakes more than three decades ago.

Denise Elaine Sexton Hartley, the youngest of 15 siblings from St. Paul, disappeared in 1993 at the age of 27. In June of that year, a severed human head was discovered near Bone Lake in Scandia, and a foot was found in Pig's Eye Lake in St. Paul a day later.

Investigators were unable to identify the remains until they harnessed investigative genetic genealogy in 2024. Ultimately, they were led to Hartley and were able to obtain a DNA sample from her daughter. Minnesota Bureau of Criminal Apprehension investigators were able to identify the remains as Hartley's, the Washington County Sheriff's Office said.

Traci Onders and the DNA Doe Project, a nonprofit that has found leads on more than 150 cases by using powerful new genetic genealogy technology.

"Somebody obviously went to great lengths to make sure that Denise's name was taken from her," Onders said. "It was very important to us to be able to give her her name back and give her family an answer."

Still, investigators say they're unsure of the manner and cause of Hartley's death. No one has been arrested.

"Cases like this stay with you," said Washington County Sheriff's Detective Clayton Evens, the lead investigator in the case. "Even after decades, there's always hope that one day the science will catch up to the questions that couldn't be answered at the time, and it finally did." 

Anyone with information connected to the case is asked to contact the Washington County Sheriff's Office at 651-430-7850.

"We're trying to make connection with any acquaintance, family member, friend, anyone we can find that had some interaction with her life," Evens said. "It would be a huge sigh of relief, not just for me, but for our entire team."