A 48-year-old man already serving a life sentence for capital murder pleaded guilty to the 1991 murder of another woman, the Arkansas State Police announced Tuesday. 

Sabrina Underwood, 19, disappeared after being dropped off in Boone County, Arkansas by her mother. Underwood planned to hitchhike to visit her boyfriend, a prison inmate, but when her boyfriend called to ask why she did not make her scheduled visit, a missing person's report was filed. Three months later, hunters found a bundle of clothes and human remains, which were later determined to be Underwood's. 

Underwood's murder remained unsolved until an inmate told Arkansas State Police investigators that Rick Allen Headley confessed to the killing in a letter written while serving a life sentence. Headley had pleaded guilty to capital murder after stabbing his estranged wife to death. He was serving his sentence in a maximum-security unit, according to police.  

Headley confirmed that he had written the letter and gave details about Underwood's death in an interview with investigators, according to officials. Headley, who claimed Underwood tried to extort him for money, also said at the time that he hoped no one else had been arrested for the murder. 

Headley was charged with first-degree murder in October 2023. On Monday, he pleaded guilty to the charge and was sentenced to 40 years in prison. 

At the time of Headley's confession, an Arkansas State Police spokesperson said that Underwood's family was "very happy" that the 32-year-old cold case had been solved. 

"We will never give up on finding justice for families like the Underwood's, who still suffer the pain of Sabrina's absence," said ASP Colonel Mike Hagar in a news release announcing Headley's sentencing. "Today, we pray for peace for those who remember and love Sabrina."

In:
• Cold Case
• Murder
• Crime

Kerry Breen

Kerry Breen is a reporter and news editor at CBSNews.com. A graduate of New York University's Arthur L. Carter School of Journalism, she previously worked at NBC News' TODAY Digital. She covers current events, breaking news and issues including substance use.

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