BROWNWOOD, Texas – A man is behind bars after reportedly confessing in church to murdering a woman last year.

CBS affiliate KTAB reports that Ryan Riggs, 21, is charged with capital murder in the death of Rhonda Chantay Blankinship whose body was found in a cellar in May 2016 in rural Brown County.

According to the station, Brown County Sheriff Vance Hill told reporters Thursday that police had not revealed to the public that Blankinship was the victim of a sexual assault, as well as homicide. But, he said, the office sent DNA evidence from that assault to a Virginia company that creates composite sketches from DNA samples. The new forensic technique predicts the ancestry and physical appearance, such as eye, skin and hair color, of an unknown person from their DNA.

The dissemination of that sketch, Hill said, eventually prompted Riggs to come forward.

According to the Brownswood Bulletin, Hill said that on Wednesday night Riggs confessed to the congregation at North Lake Community Church, where Blankinship was a fellow parishioner. Hill said he repeated the confession in front of sheriff's deputies later.

KTAB reports that Hill revealed some previous withheld information about Blankinship's death, including that she was sexually assaulted and likely beaten with a lawn mower blade that was found at the crime scene. Hill also said that she may have been killed in one place and then dumped in the cellar where she was found.

Riggs is being held without bond, reports KTAB.

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