BOISE, ID — An Idaho man has been arrested in connection with the shooting death of a woman in California more than 50 years ago, authorities said.

DNA evidence led investigators to identify 75-year-old Michael Eugene Mullen as a suspect in the 1973 death of Nina “Nadine” Fischer, the Marin County Sheriff’s Office said. Mullen was arrested Wednesday near Salmon, Idaho, and is in jail awaiting extradition to California.

Mullen’s defense attorney, Dan Brown, did not immediately respond to voice messages and emails left for him on Saturday.

Fischer was living with her husband and young daughter in San Rafael, California, when the 31-year-old was killed in November 1973, the Marin County Sheriff’s Office said in a news release. Both Fischer and her husband were Swedish citizens and were preparing to return to Sweden at the time.

Fischer’s husband found her body when he returned home from work. She had been sexually abused and shot three times; her two-year-old child was found unharmed in another room.

According to newspaper articles published after her death, police officers interviewed several witnesses – including moving workers and an appraiser who had been in the house that day – but the investigation turned up no leads and the case was closed.

In 2021, the Marin County Sheriff’s Office turned the case over to the California Department of Justice’s Family Tracing Program. The program compares DNA from crime scenes to a DNA database to find relatives of a potential suspect. After several months, the DNA revealed a possible lead, and after three more years of investigation, Mullen was identified as a suspect, the sheriff’s office said.

The Marin County District Attorney’s Office and Sheriff’s Office worked with the Idaho State Police and the Lemhi County Sheriff’s Office to arrest Mullen on suspicion of murder. He is being held in the Lemhi County Jail.