PORTLAND, Maine — A store owner who kept a woman’s body hidden in a storage unit in Lewiston refused a request to take a lie detector test 10 years after his girlfriend went missing, a retired state police detective said Wednesday.

Frank Julian declined to take a polygraph test while discussing Kitty Wardwell’s 1983 disappearance and didn’t seem to be interested in what had happened to her, said Joe Zamboni, who retired from the Maine State Police in 2004.

“The impression I got from him was that he didn’t really care,” Zamboni told The Associated Press.

Julian died this month at age 80 in Lewiston. His relatives found the body inside the storage unit he had rented since 1992. The medical examiner’s office and state police crime laboratory are using DNA to identify the remains, which police suspect are Wardwell’s.

Zamboni picked up the case after the original investigator was promoted. He said Wednesday there was never any doubt that Julian was the chief suspect in Wardwell’s disappearance 28 years ago.

Julian’s story about going with Wardwell to Salem, N.H., having a fight and then leaving her behind at a motel didn’t seem plausible to investigators because it seemed unlikely she’d leave without any contact with her daughter or family, Zamboni said. But it was difficult to advance the investigation because there was no body and no crime scene, he said.

Julian said the last time he saw Wardwell was on June 6, 1983.

Over the years, the case remained open and was treated as an unsolved homicide.

“The last person who saw them alive, you have to look at them very closely. That’s common sense,” Zamboni said. “You don’t have to be a homicide investigator to figure that out.”

The body was discovered Friday by family members cleaning out the 10-by-10 storage unit, which the storage company owner said Julian paid for in advance every three months. The body was inside an unplugged freezer, which was stashed inside the unit along with stacks of boxes and household items.

Back in 1983, Wardwell was living about 100 miles from Lewiston in the town of Holden, where she lived at Greenwood Gardens Apartments. Julian occasionally stayed with her there, police said.

After Wardwell’s disappearance, Julian put the episode behind him, buying wholesale items and selling them at a succession of variety stores. His sons still operate two stores in Lewiston and Auburn. Julian’s family repeatedly has declined to comment. Wardwell’s brother didn’t immediately return a call seeking comment on Wednesday.

DNA samples were obtained during an autopsy on Monday, but officials weren’t ready Wednesday to announce the identity of the body.

“DNA comparisons can sometimes take time. And that work is under way now,” said Stephen McCausland, spokesman for the Maine Department of Public Safety.

Associated Press news researcher Rhonda Shafner in New York contributed to this report.