PORTLAND — Detectives believed a 29-year-old woman was the victim of foul play after she was reported missing in 1983 and they interviewed her boyfriend at least twice. But the case made little headway until last week when human remains believed to be hers were discovered inside a freezer in a rental storage unit.

Maine State Police today were awaiting DNA test results to confirm the identity of a body found Friday in a storage unit in Lewiston rented by Frank Julian, who died Oct. 1 at the age of 80.

Julian was the last person known to see his girlfriend, Kitty Wardwell, alive when she disappeared 28 years ago. When questioned by police, Julian said he had last seen her on June 6, 1983, when he dropped her off at a motel in Salem, N.H., following a fight and then returned to Maine on his own.

The case was passed down to a number of investigators over the years, although it wasn’t clear Tuesday exactly why police thought Wardwell was likely a victim of foul play other than her disappearance, Maine State Police spokesman Steve McCausland said.

Detectives interviewed Julian two or three times, but evidence never reached the level to justify getting a search warrant for his property, McCausland said.

Since the gruesome discovery, Maine State Police have contacted a retired detective who was the lead investigator for a number of years to pick his brain on the case, McCausland said. As a general rule, most missing person cases are treated as unsolved homicides, he said.

“These cases — although in this case it had gone on for nearly three decades — remain open and remain active,” he said.

Julian’s relatives discovered the remains inside an unplugged freezer as they went through the 10-foot-by-10-foot storage unit he had rented since 1992 on the outskirts of Lewiston. Police are not describing the condition of the body or whether it was wrapped in anything inside the freezer.

But they say the remains could be those of Wardwell, who’s been described as Julian’s on-again, off-again girlfriend.

Her older brother, Dwight Collins, said he never met Julian but knew of him. He wonders why the case wasn’t solved years ago when it was still fresh.

“That’s the same question we all got, I guess,” said Collins, 60, of Bucksport. “I don’t know why the cops couldn’t get it.”

Police are still searching for clues and want to hear from people who lived at Greenwood Gardens Apartments in Holden back in 1983, when Wardwell was living there. Julian also had an apartment there where he sometimes stayed, McCausland said.

The results of the DNA tests and an autopsy could be released on Wednesday, officials said.

In Salem, N.H., officers were searching the attic and an on-site storage unit at the police station for any record of a missing person report on Wardwell.

“Our records division is pouring through the old paper files looking for a report, if any was taken on this,” Deputy Police Chief Shawn Patten said. “We’re not sure where it’s going to be.”