Here’s what we know about the suspect.
Police initially identified Ajayi as a person of interest Thursday after serving a search warrant at his home in the Fairpark neighborhood.
Salt Lake City Police Chief Mike Brown said at that time that Ajayi had spoken with investigators but was not in police custody.
Ajayi’s house is five miles from the park where Lueck was last seen by a Lyft driver who gave her a ride from the airport in the early morning hours of June 17.
Police said the investigation showed Ajayi and Lueck’s phones were both at the park within a minute of each other.
Ajayi denied knowing what Lueck looked like, Brown said, but investigators found several pictures of her on his phone.
A neighbor told CNN that Ajayi said he was using part of the home as an Airbnb.
Reached for comment Thursday, a spokesman for Airbnb told CNN the company was “urgently investigating.”
He allegedly burned Lueck’s personal items
Neighbors told police Ajayi used gasoline to burn something in his backyard on June 17 and 18, Brown said Friday.
Police searched the burn area and said they found “several charred items” that were consistent with Lueck’s personal items, Brown said.
They also found charred material determined to be female human tissue, he said, which matched Lueck’s DNA profile.
He worked for the US Army, Dell and Goldman Sachs
According to his LinkedIn page, Ajayi is a former information technology specialist for the US Army and recently worked for Dell and Goldman Sachs.
CNN has reached out to the US Army and Dell for comment.
His neighbor, Tom Camomile, told CNN prior to his arrest that Ajayi was a “smart guy” and a “computer geek.”
“It’s a little unnerving and unsettling” that Ajayi was connected to the case, Camomile said at that time.
“I think he’s a man of high integrity,” he said, “but you don’t know anyone.”
“Surprises pop up all the time.”
CNN’s Sara Weisfeldt, Scott McLean, Melissa Alonso and Chris Boyette contributed to this report.