Lloyd Welch pleaded guilty to the abduction and gruesome slaying of 10-year-old Katherine and 12-year-old Sheila Lyon.
A Washington-area cold case that has kept investigators up at night for four decades has all but come to a close with one man's guilty plea Tuesday.
Lloyd Welch, a 60-year-old former carnival worker with a sex predator past, entered the plea in a Virginia court, 42 years after the disappearance of Katherine and Sheila Lyon.
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The sisters vanished in 1975 from a suburban Maryland mall, sending shockwaves through the community and haunting their family ever since.
Welch was sentenced to 48 years in prison as part of a plea agreement with prosecutors, one in which he never admitted to directly killing the girls.
Instead, Welch detailed the part he said he played in a group he claims was responsible for the 10- and 12-year-old little girls.
In the days following their abduction from the Wheaton Plaza shopping mall, Welch told investigators he went into a basement where he saw his father and an uncle dismember one of the girls.
He said her remains were put into a large bag, which was taken to rural Virginia and thrown into a fire.
Investigators following up on the claims, which Welch made in 2015. No charges have been filed against his uncle, who denied any involvement. Welch's father died in the late 1990s.
Cold case detectives began focusing on Welch in 2013 after they noticed a composite sketch that resembled a 1977 mug shot of Welch in a burglary near the mall.
According to prosecutors, it was Welch who took the girls' remains to land that his family owned and burned them.
"His credibility is open for questioning. However, as the individuals that he named as his co-conspirators changed over time, what did not change was his involvement," Wes Nance, the Bedford County commonwealth’s attorney, told reporters.
The bodies of the girls have never been recovered.
In brief remarks, the girls' father thanked authorities while leaving room to wonder if the new development would help him rest better at night.
“We just want to say simply, thank you,” John Lyon said. “And it’s been a long time and we’re tired, and we just want to go home.”
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As part of his deal, Welch pleaded guilty to the unrelated sexual assaults of a young girl in Prince William County.
He will start his term for the slayings after he serves out a term for the 1997 sexual assault of a 10-year-old girl in Delaware.
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