(CBS News) BOSTON - A notorious cold case suddenly turned very hot Thursday: the case of the Boston Strangler.
Prosecutors said for the first time, DNA linked Albert DeSalvo to one of the victims with nearly 100 percent certainty. Now investigators plan to dig up DeSalvo's remains to do more tests.
For years, in the 1960s, the case of the Boston Strangler baffled police. Eleven unmarried women, ages 19 to 85, were sexually assaulted and killed in their homes. The last victim was Mary Sullivan. Casey Sherman is her nephew.
"Mary was 19 years old. She was the joy of her Irish Catholic family, grew up in Cape Cod, was a 1962 graduate of Barnstable High School," he told reporters. "She had moved up to Boston four days before she was murdered."
Unlike the other murders, police found semen in Sullivan's body and on a blanket taken from the crime scene, and preserved it. Based on that evidence, nearly 50 years later, District Attorney Daniel Conley was able to make this announcement Thursday.
"Advances in sensitivity of DNA testing have allowed us to make a familial match between biological evidence from the crime scene to the suspect in Mary Sullivan's murder," he said. "That suspect is Albert DeSalvo."
Albert DeSalvo confessed to the killings while in prison on other charges. In 1973 he was stabbed to death by a fellow inmate. DNA testing was unknown at the time, but this year scientists were able to match the preserved DNA to a DNA sample from DeSalvo's nephew -- lifted from a discarded water bottle. The match was 99.9 percent accurate.
"It's taken 49 years for to police to legitimately say they got their man," Sherman said. "And they're probably going to be able to say that very soon."
Albert DeSalvo's family declined our request to speak on camera. They remain skeptical of the findings and said in a statement, "the state has never given us enough credibility to believe anything they are doing."
Sullivan was murdered in an apartment on Charles Street. Prosecutors have said even though they have a 99.9 percent match to DeSalvo, they want to be 100 percent sure - so the excavation of his body will occur Friday.