ALLEGAN, Mich. (WOOD) — The man heading to trial in the murder of his daughter three decades ago has admitted to another horrific crime, which could be among his first in decades of suspected crimes against women.

Police told News 8 that Dennis Bowman confessed to a rape and assault incident in 1979. The victim was a 27-year-old woman from Holland.

The headline from 1979 reads, “Man sought in assault” in October of that year. The Ottawa County Sheriff’s Office was looking for a young man who raped and assaulted a Holland Township woman in her home. The description of the suspect was a white male between 25 and 30 years old with sandy hair and wire-rimmed glasses.

More than 40 years later, Dennis Bowman admitted to police that he “did bad things to her.”

The home was located near James Street and Butternut Drive. Bowman was living at a mobile home park just down the street. The reports from the time said the 27-year-old woman was bound and gagged before being sexually assaulted.

Ottawa County detectives believe Bowman is also responsible for gagging and tying up a 6-year-old during an abduction and attempted rape in September of 1989. The rope found at the scene has been tested for Bowman’s DNA but came back negative.

Police says DNA testing is advancing daily and investigators plan to retest, saying Bowman has yet to admit to this crime but remains the main suspect.

Despite the inability to prosecute Bowman, the victims need closure, and police continue to look at other Ottawa County cold cases to see if Bowman is the culprit.

While the investigations continue, Bowman is serving a life sentence for the 1980 murder of Kathleen Doyle in Norfolk, Virginia.

She was a 25-year-old wife of a U.S. Navy pilot who was deployed at the time of the murder. Following that murder, Bowman was charged for other crimes against women.

He’s is now heading to trial in Allegan County for the murder of his adopted daughter Aundria Bowman, who was 14 years old when she went missing in 1989. Prior to her disappearance, she claimed that Bowman was molesting her.

A trial date for his daughter’s murder has yet to be set.