Authorities in South Dakota announced Monday that cutting-edge DNA and genealogy testing has helped them solve the February 1968 cold case strangulation and sexual assault of a woman found dead in bed.

Rapid City Police Chief Karl Jegeris said evidence has led them to identify Eugene Carroll Field as a suspect in the unsolved murder of Gwen Miller, 60. Miller had lived alone in Rapid City as a pharmacist and was found dead after she failed to report to work, according to the Sioux Falls Argus Leader.

The news outlet reported that Field, who died in 2009 of a throat tumor, had not been previously identified as a suspect. In addition to interviewing witnesses and testing fingerprints at the time, authorities who revisited the case in 2005 and 2010 produced a suspect profile but didn’t make an arrest.

Law enforcement said their investigation was also hindered due to a 1972 flood which destroyed a lot of the original police reports, according to KELO.

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The Rapid City Journal reported that police canvassing the area spoke with a neighbor who claimed they spotted a taxi drop someone off at the victim’s home. Police checked taxi logs and had subjected some of the drivers to polygraph tests with no success. They went on to interview Miller’s neighbors and co-workers, leading them to identify pharmacy owner Michael Beckers as their main suspect.

For the first time in our dept's history, we have solved a major case using DNA genealogy. More details will be shared during a press conference this afternoon. We are pleased to have Dr. Colleen Fitzpatrick @Identifinders in Rapid City for this historic event for @RapidCityPD — Karl Jegeris (@chiefjegeris) June 17, 2019

Cold case Detective Wayne Keefe reportedly said Miller had worked for Beckers, who had made unwanted advances towards her. The detective said Beckers was often drunk when he would make unannounced taxi trips to Miller’s home.

Keefe picked up the cold case in 2016 and elicited the help of a forensic genealogy firm called IdentiFinders in 2018. Firm owner Colleen Fitzpatrick analyzed the DNA sample for its Y-DNA, leading her to locate a match to someone from northern Europe or Britain. She then uploaded the DNA to genealogy websites and discovered the samples matched men related to Field, according to the Rapid City Journal.

Using this information, Keefe reportedly analyzed public records and realized that only one man with the last name Field or Field lived near Miller. Keefe’s investigation found that Field had once rented a room in a home next to the victim and that both of his ex-wives had accused him of being abusive.

Field’s brother reportedly provided investigators with a DNA sample—which a private company ascertained had a 99.23 percent chance of being brothers with Miller’s murderer. The newspaper reported that further analysis eliminated the possibility that Field’s brother or father committed the crime.

Keefe said Monday that Field was 25 when he killed Miller. The detective said Field would’ve been charged with her first-degree murder if he was alive today.

“The family of Gwen Vivian Miller offers you our gratitude and our appreciation,” the slain woman’s niece tearfully said during Monday’s press conference. “Thank you for giving us an answer.”

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[Featured image: Eugene Field, Gwen Miller/Rapid City Police Department]