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Police believe human remains found in the back yard of a Spanish Fork home Monday may help solve a 1988 missing-persons case.

A resident was removing items from a cement cellar on the property, at 80 North and 800 East, and noticed the soil was sinking in one area of the dirt floor, according to a Spanish Fork Police Department news release.

The resident "became suspicious" about what was causing the sinking soil because he'd heard a former resident of the home was reported missing several years earlier and never found.

The man and a friend dug down into the dirt floor about 18 inches and located what appeared to be a human skull, the release said. The skull was wrapped in a blanket and plastic mesh, the release said, and the two men called police about 10:15 a.m.

In 1988, Peggy Sue Case, also known as Peggy Sue Ellsworth, and her boyfriend Michael I. Kufrin lived at the address where the remains were found Monday. Kufrin was identified in the Monday news release as a "person of interest" in Case's disappearance.

Case was last seen at a hot-tub party she and Kufrin attended July 9, 1988 in Payson, former Spanish Fork police Detective Carl Johnston told The Tribune in the past.

She allegedly was flirting with some of the men at the party, and witnesses reported certain hostility between her and Kufrin, police said, but the couple left the party together.

After the party, Kufrin called Case's workplace to report her ill. The next day, he told Case's employers she had gone out of town to buy a car, according to a previous Tribune story.

Coworkers contacted police on July 15, 1988, the release said, apparently suspicious of what they perceived as atypical behavior for Case, Johnston said. For a time, Kufrin claimed Case was staying in contact with him by phone, but he later stopped discussing the case with police.

Despite "extensively" investigating Case's disappearance, including digging through the cellar soil in 1988, police were unsuccessful in locating any evidence, the Monday news release said.

Kufrin was arrested in October 1988 in an unrelated attempted-theft case and served five years in Utah State Prison. During his incarceration, Kufrin refused to discuss the case with the Utah Board of Pardons.

After his release, Kufrin moved back to his home state of Illinois. Every year, Johnston would call Kufrin's mother to ask if she had learned anything about the case, but she never did. He would also call Kufrin every year — and typically, after he introduced himself, Kufrin would hang up, the retired detective said.

Johnston, who attended one of the parole hearings, said it was "frustrating having everything you need except her," according to a newspaper story about the hearing. Case's Utah County family had a burial plot set aside for their daughter, Johnston said.

On Monday, Johnston said that if the newly found remains turn out to be Case's, "that's a great thing for her family to have some closure." Case's body would "add some new light on some of the elements" already discovered by police, Johnston said, and police may be able to move the case forward.

Kufrin's current whereabouts were unknown Monday afternoon, the release said, and Lt. Matt Johnson said police are not asking for help from the public in locating Kufrin at this time.

The remains are being turned over to the medical examiner's office, where examiners will attempt to identify the remains, the release said.

The police's investigation is ongoing, the release said.

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