A Denton County grand jury indicted a 49-year-old man for murder on Thursday concerning the April 26 drowning of his girlfriend, 42-year-old Milcah Chepkemei Kirui of Little Elm.

Little Elm police officers said they responded to reports of a drowning at Little Elm Park in the 700 block of West Eldorado Parkway, where they found Kirui’s body.

On June 8, authorities arrested Jeffrey Demunbrun, also of Little Elm, on a manslaughter charge after a month-and-a-half-long investigation, the department said.

It is unclear why the charge was elevated to murder as police did not provide any additional details.

Demunbrun was held in the Denton County jail Friday in lieu of $200,000 bail. It is unknown whether he has an attorney.

Friends and family described Kirui as humble and easygoing, with a fun-loving personality. She was the eldest of five children.

Law enforcement officials said their investigation is ongoing.

The Dallas Express reached out to the City of Little Elm for comment, but officials were not immediately available.