On June 14, 1962, Anna Elsa Slesers' son entered her third-floor apartment in Boston.
After a quick look around the home, the 23-year-old found his mother's body on the kitchen floor. Her blue house coat had been ripped open; its belt had been used to strangle her.
It had then been tied into a bow around her neck, as if the killer was leaving a gift for whoever was unfortunate enough to come across the body.
A single woman in her mid-50s, Slesers didn't have any enemies, her son told the Boston Globe.
Watch the trailer for Boston Strangler. Post continues below.
Although it appeared Slesers had been sexually assaulted using an unknown object, police put the crime down to a burglary gone wrong.
Two weeks later, in the Boston suburb of Back Bay, 85-year-old Mary Mullen was found dead on her sofa. She'd died of a heart attack. Her apartment had been ransacked and police concluded the 85-year-old was "frightened to death" by an intruder.
Two days later, a third victim was discovered. Nina Nichols' body was found on her bedroom floor. She was wearing a pink flannel robe that was torn from the waist down. Around her neck were two stockings, tightly drawn into a bow. She had been sexually assaulted with a wine bottle.
The same day, Helen Blake, a 65-year-old nurse, was found facedown on her bed, her flannel pyjama bottoms on the floor, and a stocking and a bra tied around her neck. Another bow.
“The stocking was the instrument of death,” a Boston Globe reporter wrote at the time. “The bra knotted at the nape as though the killer wanted to make sure of his work.”
It was around this time that the people of Boston began to wonder whether there could be a serial killer living among them. Due to the victims' ages, the killer was soon dubbed 'The Mother Killer'.
But by December, younger women were also being attacked and sexually assaulted, and more were killed.
In 1963, Jean Cole and Loretta McLaughlin, two investigative reporters for the Record American, wrote a four-part series about the killer, dubbing him 'The Boston Strangler'. (Their story has been turned into the new movie, Boston Strangler, starring Keira Knightley. It premieres on Disney+ on March 17.)
There was never any sign of forced entry at the crime scenes, leading detectives to believe the killer posed as a repairman, delivery man or some other kind of service worker to gain entry into the women's homes.
Deadbolt locks and door chains flew off the shelves as the city's female population lived in terror of becoming the Strangler's next victim. There were so many requests for guard dogs that the Animal Rescue League ran out.
"You're asking if people were scared?" a veteran reporter told Mass Moments 40 years later. "I covered the murders and I was scared. I had an elderly mother in Medford, and after the fifth strangling, I was so scared I went over to her apartment and installed two dead bolts... But after a while you couldn't buy 'em. Sold out."
The city became obsessed with the serial killer and details of the Strangler's latest victim were splashed across the front page of the newspaper every morning.
"Every time you picked up a newspaper there was a strangling story. We just kept it up, and there were hawkers on street corners, yelling, 'Extra! Extra! Strangler strikes again!'" reporter Eddie Corsetti recalled to Mass Moments.
Detectives worked around the clock to find the Strangler and questions began to arise as to whether the murders were connected to earlier accounts about a man in green - dubbed 'The Green Man' - who would offer to paint people's apartments, then rob and sexually assault them.
When the Strangler killed for the final time, murdering 19-year-old Mary Sullivan in January 1964, police were no closer to identifying him.
Later that year, in October, a man named Albert DeSalvo was arrested for impersonating a police detective, breaking into a woman's apartment, tying her up and assaulting her.
During questioning, he told the police he had broken into hundreds of homes and raped four women.
“If you knew the whole story, you wouldn’t believe it… It’ll all come out," he bragged.
Police didn't take DeSalvo seriously at first. He was known to talk himself up and they believed he was just trying to take credit for the Strangler's crimes. Plus, his name had never once come up during their investigation.
They sent him to the Bridgewater State Hospital for the Criminally Insane, where he befriended convicted murderer George Nassar.
Police convinced Nassar to get DeSalvo to talk him. He did, and they soon had more than enough to question him again.
“He convinced me by the description," Nassar later told WBZ-TV. "He was getting it off his chest. I was the first person, apparently, to whom he had really spoken about specifics of each crime."
On March 6, 1965, Albert DeSalvo formally confessed to being the Boston Strangler. He said he had killed 13 women, including Mary Mullens, who he said died of a heart attack in his arms.
But while he knew specific details about each murder, DeSalvo wasn't charged with the Strangler's crimes. Instead, he was found guilty of robbery and assault, and was sentenced to life in prison for 'The Green Man' rapes.
In 2013, DNA connected DeSalvo to at least one of the Boston Strangler murders. However, he's never been formally linked to all the victims.
Sixty years on, there's still an air of mystery around the Boston Strangler.
Was Albert DeSalvo really the man who terrorised the city for two years? Or did the killer continue to live among the residents as they unknowingly walked the streets of Boston, believing they were finally safe?
Boston Strangler is streaming on Disney+ from Friday, March 17.
Feature image: Disney+.
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