Investigators in Mississippi uncovered the body of a woman on Sunday after they were tipped to the location by a death row inmate who confessed to killing his sister-in-law just before his execution last month.

David Neal Cox was convicted of killing his wife, Kim Kirk Cox, and sexually assaulting his stepdaughter in 2010 and later told the Mississippi Supreme Court he was “worthy of death,” as CrimeOnline previously reported.

Before his November 17 execution, Cox confessed to his lawyers that he killed Felecia Cox, 40, in 2007 and detailed the location of her body in a letter that he asked not to be opened until after his death.

Investigators had always suspected David Cox was connected with Felecia Cox’s disappearance but never had enough evidence to charge him.

WTVA said the remains were found on land the family once owned near Pontotoc.

The station said that members of Cox’s family, a Mississippi State University anthropology professor and some students were at the scene when the remains were uncovered, along with Pontotoc County Sheriff Leo Mask and District Attorney John Weddle.

The remains are being taken to the state forensic laboratory in Biloxi for positive identification.

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[Feature Photo: Felicia Cox/Family Handout; David Cox/Handout]