(SALT LAKE CITY) — A Utah man will spend life in prison as part of his guilty plea in the killing of college student Mackenzie Lueck, whose charred body was left in a shallow grave, prosecutors said.

Ayoola Ajayi on Wednesday pleaded guilty to aggravated murder and desecration of a human body in connection to Lueck’s June 2019 slaying.

Lueck, a 23-year-old kinesiology major at the University of Utah, met Ajayi on a “sugar daddy” dating website called Seeking Arrangement, according to Ajayi’s lawyer.

Lueck had been missing for nearly two weeks by the time Ajayi was arrested.

Lueck’s charred remains were recovered in July 2019 in a shallow grave in Logan Canyon. Her arms were bound behind her back by a zip tie and rope, prosecutors said.

No motive was released, prosecutors said.

“Ayoola Ajayi also pled guilty to Forcible Sex Abuse in a separate case,” Salt Lake County District Attorney Sim Gill said in a statement on Wednesday. “Part of the Plea Agreement is that Ayoola Ajayi will spend his life in prison without the possibility of parole.”

“The entry of the pleas today starts the process of bringing some closure and a measure of justice to the Lueck family,” Gill added.

Ajayi will be formally sentenced on Oct. 23, prosecutors said. His attorney could not immediately be reached by ABC News for comment.

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