A 76-year-old serial killer serving life for murdering nearly a half-dozen women and girls in New Jersey and New York since the 1960s admitted on Monday he strangled a woman in a Nassau County mall parking lot more than 50 years ago -- and confessed to four other slayings, prosecutors announced.
Richard Cottingham, currently serving a life sentence in New Jersey state prison for his past convictions, has claimed responsibility for up to 100 murders over the past few decades. He pleaded guilty Monday to second-degree murder in the February 1968 killing of Diane Cusick, a case in connection with which he was indicted this past June.
As part of a plea deal, Cottingham received immunity from prosecution for the four other killings.
The so-called "Torso Killer" or "Times Square Killer" also confessed to four previously unsolved slayings from the 1970s. Those include the May 1972 and July 1972 killings of Mary Beth Heinz and Laverne Moy as well as the 1970s murders of Sheila Hyman and Marita Rosado Nieves. He won't be prosecuted additionally for those cases but will have another 25-year sentence added to his current life sentence as part of the plea deal unveiled Monday.
Cusick was a 23-year-old dance teacher and mother of one when she was found beaten, raped and duct-taped in her car in Valley Stream's Green Acres Mall parking lot that year.
Get Tri-state area news delivered to your inbox. Sign up for NBC New York's News Headlines newsletter.
It was two days after Valentine's Day.
"Today is one of the most emotional days we’ve ever had in the Nassau County district attorney’s office," District Attorney Anne Donnelly said at a news conference where she was joined by several family members of Cottingham’s victims. "In the case of Diane Cusick, her family has waited nearly 55 years for someone to be held accountable for her death."
Donnelly said Cottingham, believed to be one of the United States' most prolific serial killers, “has caused irreparable harm to so many people and so many families, there’s almost nothing I can say to give comfort to anyone.”
Cottingham allegedly pretended to be a security guard or police officer to get Cusick to go with him. Investigators long believed he had done the same for other homicide victims. This past summer, five open cases connected to Cottingham's DNA saw more testing. It's not clear if four of those five cases were the new victims identified Monday.
Though he has been behind bars for decades, prosecutors say they continue to work to bring closure to families.
“Diane Cusick, a 23-year-old mother, called her parents on the night of February 15, 1968, to tell them she was going to the mall to purchase shoes. She never returned home," Donnelly said in announcing the June indictment. "Cusick was allegedly bound and murdered by Richard Cottingham."
"It was only through advances in DNA technology that the NCDA and our partners at the Nassau County Police Department, could solve this 54-year-old cold case and identify a suspect in Ms. Cusick’s tragic death," Donnelly added. "We make a promise to her surviving daughter today: we will bring her mother’s killer to justice."
Authorities believe Cusick left her job at a children’s dance school and then stopped at the mall to buy a pair of dance shoes when Cottingham followed her out to her car. Her parents reported her missing when she didn't come home. They were the ones to find her car at the mall parking lot -- and they were the ones to find her body in the backseat.
Police believe Cottingham, while pretending to be an officer, accused her of stealing and then overpowered the the 98-pound woman. The medical examiner concluded that Cusick had been beaten in the face and head and was suffocated. She had defensive wounds on her hands and police were able to collect DNA evidence at the scene. At the time, however, DNA testing did not exist.
Cottingham was working as a computer programmer for a health insurance company in New York at the time of Cusick’s death.
It was Cusick's daughter, Darlene Altman, who stood alongside law enforcement Wednesday as they announced the indictment.
"I never thought I would see this day but all these people got justice for my mom," daughter Darlene Altman said. "It was overwhelming to see him on video in court with a dead stare."
One of New Jersey's most notorious serial killers, Cottingham was nicknamed "The Torso Killer" because he was known for dismembering his victims, according to NorthJersey.com. He has admitted to killing at least a dozen women since the 1960s.
Cottingham pleaded guilty last year in New Jersey to the 1974 murders of two teenage friends who went to the mall one day for bathing suits and never returned.
The teenagers, 17-year-old Mary Ann Pryor and 16-year-old Lorraine Marie Kelly, were among at least a dozen victims linked to Cottingham over the years. He admitted to murdering nine women in the 1960s and 70s but the death toll is thought to be higher.
In the early 1980s, Cottingham was convicted of killing five women — three in New York and two in Bergen County — and in 2010, he confessed to killing a woman in northern New Jersey in 1967. He has been jailed since 1981.
Cottingham has claimed to be responsible for up to 100 murders. Pryor and Kelly were found five days after they went missing — their nude, battered bodies discovered facedown in the woods of northern New Jersey. Kelly was reportedly found with a beaded bracelet and a necklace that read “Lorraine and Ricky,” a reference to her boyfriend.
Pryor was discovered with a gold cross, a gift from her godfather.