DNA evidence found on a discarded coffee cup led police to charge a Pennsylvania man with the decades-old murder of a woman who was found dead in her apartment in 1975, officials said Monday. 

David Sinopoli, 68, of Lancaster, is charged with homicide in the 1975 death of Lindy Sue Beichler, the Lancaster County District Attorney’s Office said. Police arrested him at his home Sunday, and he is being held without bail. 

"Lindy Sue Beichler was 19 when her life was brutally taken away from her 46 years ago in the sanctity of her own home," Lancaster County District Attorney Heather Adams said. "This arrest marks the beginning of the criminal process in Lancaster County’s oldest cold case homicide, and we hope that it brings some sense of relief to the victim’s loved ones and to community members who for the last 46 years had no answers."

Beichler, 19, was found dead inside her Manor Township home on Dec. 5, 1975. She was stabbed multiple times and was discovered by her aunt. 

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Investigators discovered blood on the front door and the entrance to the apartment. Inside, they found a knife sticking out of Beichler's neck and a tea towel wrapped around the wooden handle. The knife matched one of Beichler's knives in her kitchen, investigators said. 

In 1997, a DNA profile was created from evidence collected from the crime scene – Beichler's underwear was determined to contain semen, authorities said. 

The district attorney's cold case unit took over the case in 2019 and had a laboratory analyze the DNA collected. Composites revealed three characteristics of the suspect: skin tone, eye color and hair color. 

Further genetic testing identified Sinopoli through his Italian ancestry as a possible person of interest, authorities said. 

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On Feb. 11, investigators collected a coffee cup that Sinopoli had used and then threw in the trash at Philadelphia International Airport. Further research matched his DNA and the semen found on Beichler's underwear. 

"There has been a never-ending pursuit of justice in this case that has led us to identifying and arresting Sinopoli," Adams said. "Lindy Sue Beichler was on the minds of many throughout the years. Certainly, law enforcement never forgot about Lindy Sue, and this arrest marks the first step to obtaining justice for her and holding her killer responsible."