Killer identified half a century after young mom murdered in her home, New Hampshire authorities say

A decades-old New Hampshire cold case has been solved with modern DNA testing, authorities said Monday.

Judith Lord, 22, was found dead in her Concord apartment on May 20, 1975 when a staff member entered the unit to collect unpaid rent, according to a news release from the New Hampshire Department of Justice. The staff member also heard a baby crying inside the unit, according to the state attorney general's report .

Investigators determined that there had been a violent struggle, and that Lord had been sexually assaulted and strangled to death. Her 20-month-old son was found unharmed in his crib in another room of the apartment.

Investigators recovered forensic evidence, including hair and seminal fluid, from the crime scene, authorities said. Investigators focused on three suspe