A Minnesota man has been accused of violently stabbing a woman to death decades ago after authorities identified him using DNA from a genealogy website and a messy napkin, the Daily Beast reports.

Jerry Westrom, 52, was charged this week in connection with the 1993 homicide of Jeanne Ann “Jeanie” Childs in Minneapolis.

Investigators zeroed in on Westrom after they compared DNA evidence from the crime scene to DNA submitted through an internet genealogy website, an emerging tactic in law enforcement in solve cold cases. Two potential matches were found and police focused on Westrom first because he lived the closest, just 35 miles north of Minneapolis in the city of Isanti.

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Here's a family provided photo showing 1993 cold case murder victim, Jeanne Childs step children at her Isanti gravesite. Turns out her suspected killer lived just two miles away. If DNA has indeed led investigators to the right guy, he would have driven past cemetery regularly. pic.twitter.com/l8GaxwTIte — Paul Blume (@PaulBlume_FOX9) February 14, 2019

Childs was 35 years old and worked as a prostitute when she was killed. Police were called to her apartment after neighbors living below her reported that water was seeping through the ceiling. Childs was found in her shower with numerous stab wounds and wearing only socks. The water was still running and blood was found throughout her unit.

Investigators found semen on clothes and towels. DNA samples were also taken from blood.

At the time of the killing, Minnesota did not yet allow DNA to be used as evidence in court and there was no functional way to link the DNA to a suspect. The case was eventually closed and deemed unsolved.

Authorities would eventually open the case back up, getting the DNA samples tested and comparing them to online genealogy websites. After Westrom was deemed a primary suspect, police began surveillance on him. They needed a better DNA sample before they could make an arrest.

Then Westrom went to a local hockey game, ordered a hot dog and threw away a messy napkin he used to wipe his mouth. Investigators made their move, recovering the napkin from the trash and getting it tested.

It was a sufficient match for an arrest warrant, and once Westrom was in handcuffs, police took another DNA test that matched perfectly.

Westrom has denied knowing Childs and claims he doesn’t know how his DNA got into the apartment, although his father has confirmed that his son did live in Minneapolis in 1993.

Westrom was released from jail Friday night after posting $500,000 in bail, according to WCCO-TV. His next court appearance is March 13.

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[Feature Photo: Jerry Westrom/Hennepin County Jail]