The map provided by David Neal Cox before his execution.
CNN  — 

Investigators in Mississippi found remains Sunday at a site they found using a map provided by a man executed last month who said that’s where they would find the body of Felicia Cox, who has been missing since July 2007, prosecutors said.

David Neal Cox gave the map and a letter to his attorneys from the Mississippi Office of Capital Post-Conviction Counsel prior to his execution on November 17, District Attorney John Weddle said in a news release.

Cox was on death row after pleading guilty to murdering his estranged wife and sexually assaulting her 12-year-old daughter. He was sentenced to death for the capital murder conviction in 2012, according to court records.

Cox had previously been a suspect in his sister-in-law Felicia Cox’s disappearance, Weddle said in the news release.

Cox’s attorneys began communicating with Weddle’s office during the summer “regarding the possibility of a disclosure … of the whereabouts of the body of Felicia Cox,” Weddle said.

Prosecutors agreed to grant Cox immunity in Felicia Cox’s disappearance in exchange for him disclosing the location of her body. Cox agreed to waive attorney-client privilege, allowing his lawyers to hand over the information after his death, Waddle said.

After prosecutors received the information, they gathered a team for a search of the site in Pontotoc County, Mississippi. That team included members of the Mississippi State University departments of Archaeology and Anthropology who used ground-penetrating radar to help guide the recovery team.

Investigators also used satellite imagery to compare the location mapped out by Cox in 2007, when Felicia Cox went missing, to what it looks like today, the news release said. “It was consistent with what he said,” Weddle said.

Satellite images compare site of search in 2007 and present day.

On Sunday investigators found remains at the site and sent them to the Mississippi Medical Examiner’s office for an autopsy and DNA testing to confirm the identity, Waddle said in the release.

Felicia Cox’s daughter, Amber Miskelly and other family members were at the site and were able to view the recovery, the release said.

The Mississippi Office of Capital Post-Conviction Counsel said in a Facebook post it “appreciates the hard work, respect, and professionalism provided by the District Attorney’s Office for the First Circuit Court District.”

CNN has reached out to the Pontotoc County Coroner’s Office and the Pontotoc County Sheriff’s Office for comment.

CNN’s Chris Boyette and Joe Sutton contributed to this report.