NASSAU COUNTY, Long Island (WABC) -- A serial killer known as the "Torso Killer" admitted Monday to killing a 23-year-old woman outside a Long Island shopping mall in 1968 and four other women decades ago.
Richard Cottingham was arraigned earlier this year on a second-degree murder charge in connection with Diane Cusick's death during a trip she made to buy shoes at the suburban Green Acres Mall. Cottingham is believed to be one of America's most prolific serial killers and has already been convicted in 11 other killings.
Appearing virtually from a New Jersey prison for the Nassau County Court hearing, Cottingham was sentenced to 25 years to life behind bars for Cusick's slaying. He received immunity from prosecution for the four other killings he admitted to as part of his plea deal in Cusick's death.
Cottingham has claimed he was responsible for up to 100 homicides, though authorities in New York and New Jersey have officially linked him to only a dozen so far. He has been imprisoned since 1980, when he was arrested after a motel maid heard a woman screaming inside his room. Authorities found the woman alive but handcuffed and suffering from bite marks and knife wounds.
Cusick was a children's dance instructor at the time of her death. She went to the Green Acres mall to buy new dance shoes and then was found lifeless in her backseat.
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.
The DNA was entered into a national database in 2016 when Cottingham pleaded guilty to another killing in New Jersey. In 2021, police in Nassau County received a tip that a suspect who might be responsible for killings in the suburban county was locked up in New Jersey. They began running DNA tests again on cold cases and came up with a match to Cottingham.
The Nassau District attorney says this is likely the oldest DNA hit to lead to a prosecution in this country.
After the indictment back in March, Cusick's daughter, who was just 4 at the time of her death, said she never thought her mother's killer would be brought to justice.
"The pain you and your family have experienced the last 50 years is beyond our comprehension. Our best people are working on this case and we will get justice for your mother," Nassau County District Attorney Anne Donnelly said to Cusick.
Detectives say Cottingham would target young women, oftentimes posing as mall security.
"He would confront people coming out of the mall. He would accuse them of stealing something and once he got their attention, he'd commit this violent act," Detective Captain Steven Fitzpatrick said.
Cottingham was working as a computer programmer for a health insurance company in New York at the time of Cusick's death.
Cottingham is already serving a life sentence for other killings.
(The Associated Press contributed to this report.)
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