A witness said that the homeowner rushed into the city building Monday and said, "You've got to come and see what I just found in my basement."
Police say the remains were found Monday afternoon when the owners were cleaning the lower level of the home to begin remodeling. The remains were sent to the state medical examiner's office for an autopsy.
County assessor's officials say the house was bought in May after sitting empty since 2009. The previous owner, Mark Edgar Koster, bought the house in 1997 after it was split from a neighboring property. A roommate reportedly lived there with him for a time. Koster, who was age 58 at the time, went missing on the 4th of July in 2009 and was legally declared dead in October of 2011, according to the website iowacoldcases.org. The website reported that he was last seen with a friend from Florida. After he had gone missing, a search of the home found his clothing and personal effects including a tobacco pipe he normally carried with him still in place and his vehicle in the garage. Police, however, said that the evidence indicated he had left the residence. There were no signs of a crime or anything suspicious in the house, and the Iowa Division of Criminal Investigation took fingerprints and DNA samples to put into the missing persons system. There had been no activity involving Koster's bank account or debit card since he had disappeared.
Sac City Police say the remains could be those of Koster, but are not commenting about whether foul play could be involved in the death. They will review the entire investigation from 2009, and re-interview friends and family of Koster, according to Chief John Thomsen.
"Common sense would tell you it's a very good possibility it's him, but we have no idea. I mean, he had another subject who was supposedly living with him at the time," Thomsen said. The other individual has yet to be identified.
Daniel Koster, the victim's brother, only learned that his brother was missing when the Sac City utility department contacted him about his unpaid utility bills at the Sac City house.
After a petition from family in order to settle Koster's affairs, a court-appointed panel decided more than two years after the disappearance that evidence indicated Koster had died by unknown "accidental or violent means."
Koster remains listed on the Iowa Dept. of Public Safety Missing Persons Information Clearinghouse.
The Sac County sheriff's office and the Iowa Division of Criminal Investigation are assisting police in the investigation.