STILLWATER, Okla. — Law enforcement authorities are investigating a registered sex offender who is jailed in Stillwater, Oklahoma, for the alleged murder of a former Kansas woman.

On June 3, the Payne County Oklahoma Sheriff’s Office requested that the Oklahoma State Bureau of Investigation assist with an investigation into a missing person case that evolved into a homicide investigation, according to a media release from the Oklahoma State Bureau of Investigation.

Chelsey Chaffin, 29, formerly of Hutchinson, last spoke to her mom by text during the evening hours of May 25. That was the last time she was heard from by friends or family, according to the release.

On May 24, Chaffin had moved to a residence in Stillwater. The residence belonged to 54-year-old Earl Oswalt, who worked with Chaffin at a tile company in Stillwater.

The Payne County Sheriff’s Office and the OSBI followed up on dozens of leads in the missing person case that ultimately led to the arrest of Oswalt for murder.

Investigators say he killed Chaffin in the early hours of May 26. At approximately 1 a.m. on May 27, her body was dumped over a bridge into the Cimarron River.

Oswalt is a registered sex offender who spent 20 years in prison on a 60-year sentence for rape in the first degree. He was paroled in 2017.

The search continues in hopes of recovering Chaffin’s body.