Riverside County Cold Case Victim Identified After 50 Years

A Riverside County cold case dating back more than 50 years has taken a major step forward after investigators identified the woman whose partially buried body was discovered in Desert Hot Springs in 1974.

The Riverside County Regional Cold Case Homicide Team says the victim was 19-year-old Rebecca Jean McMahon.

McMahon was reported missing by her family in July 1973. She was last seen in Bell Gardens and had reportedly told her family she was planning to travel to Palm Springs.

Months later, on January 19, 1974, McMahon’s partially buried body was discovered in Desert Hot Springs. Investigators were unable to identify her for decades.

The case was reexamined in 2024 as advances in forensic science and genetic genealogy provided investigators with new tools to identify unidentified remains.

DNA from McMahon’s remains was analyzed by a forensic laboratory and uploaded to an ancestry database. Investigators were able to identify a possible relative through the genetic information. A subsequent DNA comparison confirmed the woman’s identity as McMahon.

The identification gives investigators new information as they continue working to determine what happened to McMahon and who may have been responsible for her death.

The Riverside County Regional Cold Case Homicide Team is asking anyone with information about McMahon, her disappearance or the circumstances surrounding her death to come forward.

Anyone with information is encouraged to contact the Riverside County Regional Cold Case Homicide Team.