A homeless man charged in the killing of a former Iowa State University golfer has pleaded guilty to first-degree murder.

Collin Richards, 22, entered the plea during a hearing Friday, according to the Des Moines Register. He faces a mandatory sentence of life in prison when he's sentenced Aug. 23. Richards had previously pleaded not guilty to the charge and was set to stand trial in September.

Police say Richards fatally stabbed 22-year-old Celia Barquín Arozamena last September while she was playing a round at a public course in Ames, near the university campus, and leaving her body in a pond on the course. Investigators say Richards he had been staying in a small homeless encampment in the woods near the public course.

Barquín Arozamena was a top golfer in Spain as a teenager and came to Iowa State to pursue her career.

"Today we honor the life and memory of Celia Barquin Arozamena, by announcing that justice has been served in her case," Story County Attorney Jessica Reynolds said in a statement. "There were no plea offers made in this case. ... My heart is with Celia's family today with the hope that this result will bring them some level of comfort."

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