Teresa Broudreaux, 20, was five months pregnant with her second child when she was killed.
A 65-year-old registered sex offender was arrested in the 37-year-old cold case killing of a young mom who was expecting her second child when she was murdered, officials said.
After getting into an argument with her new husband, Ronnie Fematt, 20-year-old Teresa Broudreaux decided to spend time at her nearby sister’s house in March of 1980.
Broudreaux left her sister’s home to go back to her husband, but she was never seen alive again.
Her nude, lifeless body was found early in the morning of March 4, 1980 along the shoreline of Malaga Cove Beach in Palos Verdes Estates.
The young mother, who had a 4-year-old daughter and was five months pregnant with her second child, had been beaten over the head and killed.
Investigators worked to pinpoint who killed Broudreaux, and though they followed up on numerous leads, the case eventually went cold.
Read: Cops Announce Arrest in 1992 Cold Case Murder of Teacher's Aide: 'We Got You'
But after 37 years, advances in DNA technology made it possible for the Los Angeles sheriff’s investigators to say they'd caught the man allegedly responsible.
“These cases wait for the powerful combination of a detective who never gives up, a witness with a guilty conscience, a suspect with self-serving interest, or in this case, new DNA technology,” Sheriff Jim McDonnell said.
Cops say evidence collected at the crime scene in 1980 eventually linked to Robert Yniguez, whose DNA was on file for a prior sex offense.
He had been arrested in 1981 and suspected of sexually assaulting a young woman, but the charges then were dropped after the alleged victim stopped cooperating, police said.
Yniguez was arrested again in 1982 and served eight years in prison after being convicted of rape.
Since his release, he has gotten married and has worked as a construction worker, authorities said.
Yniguez had been questioned several times over the years about Broudreaux’s killing, police said.
Authorities said Broudreaux died from a skull fracture and that the motive in the case appeared to be sexual assault, but they could not prove if one occurred.
Read: Bizarre Cold Case Clown Murder Comes to a Close 27 Years Later: Cops
The arrest was bittersweet for Broudreaux’s husband, Ronnie Fematt, who had been left with the torturous question of who killed his wife and their unborn child.
“It’s been a long time for this day,” said Fematt. “It’s been a long time for what I’ve been through.”
Fematt was 21 years old when his wife was killed.
Once considered a suspect in the case, Fematt stood with the Los Angeles Sheriff’s Department as they announced they had made an arrest in his wife’s death, CBS News reported.
“There was nobody to hear her cry, nobody to hear her screams, nobody to help her,” Fematt said, choking back tears as he spoke to reporters.
Fematt and Broudreaux met while she was working at a fast food restaurant, and the pair dated for a few years before they were married. They were expecting a little girl.
“When she bled out, they baby died,” Fematt said. “I think of that all the time.”
Yniguez is being held in lieu of $1 million bail. He is set to be arraigned on Monday.
Watch: Man Convicted in 1979 Cold Case Disappearance of Etan Patz