In a breakthrough that resolved a decades-old mystery, American police identified and arrested a suspect in a 1980 murder case, thanks to a DNA sample recovered from a cigarette butt.

The Kent Police Department in Washington State announced that Kenneth Duane Kundert, 65, has been charged with the murder of Dorothy “Dottie” Maria Silzel, who was killed at her home in Kent on February 26, 1980.

Silzel, a 30-year-old Boeing training supervisor, was found dead from strangulation, a head injury, and sexual assault.

Silzel was last seen leaving her job at a local pizza place three nights before her death.

Advances in DNA technology in 2016 allowed investigators to obtain a partial DNA profile from a bathrobe found at the crime scene.

This profile was matched to an individual identified as "Person A," but initial attempts to identify the suspect through DNA comparisons were unsuccessful.

In 2022, investigators utilized genetic genealogy to narrow down potential suspects. This technique, which compares unidentified DNA with databases to find relatives, led them to Kundert and his brother, both of whom were residing in Arkansas.

By September 2023, investigators had Kundert and his brother in custody on unrelated charges.

While Kundert’s brother voluntarily provided a DNA sample, Kundert refused.

Despite this, police found that Kundert's DNA matched "Person A" when a cigarette butt discarded by Kundert was tested in March 2024.

Kent Police, with the help of the FBI and local authorities, had been monitoring Kundert in Clinton, Arkansas. The DNA from the cigarette butt confirmed Kundert's involvement in the crime.

Currently held in an Arkansas county jail, Kundert is awaiting extradition to Washington. He faces first-degree murder charges in King County, with bail set at USD 3 million.

This development marks a significant resolution to a case that had remained unsolved for over 40 years.