Utah prosecutors on Tuesday filed additional charges against the man suspected of killing a University of Utah student who was found dead last month with her arms bound behind her back, after child pornography was found on his computer.

Ayoola Ajayi, 31, was already facing charges in the death of Mackenzie Lueck when the Salt Lake City District Attorney's Office filed 19 counts of sexual exploitation of a minor against him.

The charges were filed after investigators found "numerous" images of children as young as 4 engaged in sex acts, prosecutors said in a statement.

SUSPECT IN MACKENZIE LUECK KILLING WANTED SECRET ROOM BUILT, CONTRACTOR SAYS

Ajayi is charged with aggravated murder, aggravated kidnapping, obstruction of justice and desecration of a human body. Prosecutors have not disclosed a motive for the killing.

Lueck, 23, was last seen alive on June 17 near a park in Salt Lake City where she had been dropped off by a Lyft driver. Ajayi was the last person with whom she's known to have had contact, investigators said. Phone records indicate he was in the area where Lueck was last seen, according to police.

She was found 80 miles north of the city last month, her arms bound with a zip tie and a two-inch hole in her skull, Salt Lake County District Attorney Sim Gill said.

Court documents show that investigators searched social media and dating sites while trying to find a link between Lueck and Ajayi, including one called Seeking Arrangement, which bills itself as a way for wealthy "sugar daddies" to meet women known as "sugar babies."

Brian Wolf, a Utah handyman, told Fox News last month that Ajayi recently asked him to build a secret, soundproof room in his basement, complete with hooks on the walls. Wolf said Ajayi asked him about “building this weird room” in a small space in the basement, and said some of the requests had set off alarms with him.

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Ajayi was banned from the University of Utah campus in 2012 after his arrest by campus police for alleged possession of stolen property.

Ajayi was employed as an information technology worker who had stints with high-profile companies and was briefly in the Army National Guard. He remains in police custody and has not pleaded to any charges against him.

Fox News' Cristina Corbin, Ryan Gaydos and The Associated Press contributed to his report.