A serial killer on death row in Oklahoma pleaded guilty Wednesday to three cold case murders in Texas and sentenced to life in prison. 

William Reece, 62, appeared in a Galveston County courtroom when he admitted to killing 12-year-old Laura Kate Smither and 17-year-old Jessica Lee Cain, Fox Houston reported. Later that day, he was in a Brazoria County courtroom where he also admitted to killing 20-year-old Kelli Ann Cox. 

He received a life sentence in each of the cases. 

The violent crime spree occurred during a five-month span in 1997, during which time Reece killed four people and kidnapped another. He had previously served time in an Oklahoma prison for raping two women. 

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Texas cold case murders

Jessica Lee Cain, Kelli Ann Cox and Laura Smither were killed by William Reece in Texas decades ago. Reece admitted to the murders on Wednesday.  (Texas DPS and Oklahoma State Bureau of Investigation)

In 1998, he was convicted in the aggravated kidnapping of Sandra Sapaugh. He was sentenced to 60 years in prison. 

Reece began cooperating with prosecutors a few years ago and confessed to murders in Texas in exchange for a more lenient sentence. He was temporarily released from state prison into local law enforcement custody to help with the searches for Cain and Cox.

In 2021, he was sentenced to death in Oklahoma for the death of Tiffany Johnson in Oklahoma City.

Smither's remains were found in 1997, more than two weeks after she failed to return from a morning run in the Houston suburb of Friendswood. 

In July 1997, Cox left a tour of the Denton, Texas jail with her fellow University of North Texas classmates when she vanished. When she got to her car, she realized she left her keys inside. She walked across the street to a gas station to call her boyfriend and was never seen again. 

Serial killer in Texas an Oklahoma

(Fox Houston)

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Cain disappeared after attending a party at a restaurant on Aug. 17, 1997. Her father's truck, which she was driving, was found abandoned. In 2016, Reece led authorities to her remains in Houston and Cox's remains in Brazoria County.