On Monday, almost exactly a month after 20-year-old college sophomore Mollie Tibbetts vanished from her rural town of Brooklyn, Iowa, authorities interviewed the man they would soon accuse of murdering her.
The sequence of events that led to Tuesday’s break in the baffling mystery — first the discovery of Tibbetts’ remains in a local field that morning; then the announcement that suspect Cristhian Bahena Rivera was being charged with her first-degree murder — is detailed in an arrest warrant affidavit obtained by PEOPLE.
According to the affidavit, Rivera, 24, is the one who led investigators to Tibbetts’ dead body, where he had allegedly concealed it with plants. (Confirmation was pending but police are confident the remains belong to Tibbetts, a source previously told PEOPLE.)
The affidavit also shows Rivera’s alleged explanation for Tibbetts’ death: how he said he pursued her while she was out for her regular evening jog and then later found her body dead in his trunk, her head bloody.
Rivera allegedly said that he had “blocked” himself from remembering the time between — “which is what he does when he gets very upset,” according to the arrest affidavit.
Rivera “kept to himself” and had lived in the area between four and seven years, state authorities said Tuesday. He’d worked for four years on an area farm, according to the Des Moines Register, which reports that the company said he had been vetted before being hired.
A motive in Tibbetts’ slaying has not been announced. An autopsy is reportedly scheduled for Wednesday.
“It’s not the ending we all hoped for at all,” Tibbetts’ friend Alyssa King told PEOPLE not long after her body was found.
A Run Goes Awry
Tibbetts, a psychology student entering her second year at the University of Iowa, was reported missing on July 19 after failing to show up for work.
She was last seen alive the night before, on her regular jog around Brooklyn, a community of some 1,500 people. She’d been staying with her boyfriend in his brother’s home and was dog-sitting for them.
Then she disappeared — a mystery that lasted for weeks.
But investigator comments in Rivera’s warrant affidavit, released Tuesday, shed light on Tibbetts’ final moments. According to detectives, Rivera was crucially linked to a dark-colored Chevy Malibu that was seen on July 18 “driving back and forth” in the same area of Brooklyn where Tibbetts had been running.
Rivera was then interviewed by authorities on Monday, the affidavit states. Under questioning he allegedly admitted crossing paths in Brooklyn with a “female jogger” — believed to be Tibbetts — whom he followed in his car before getting out and then following “behind and alongside” her.
His behavior unnerved Tibbetts, however, and she threatened to call the police, according to Rivera’s alleged account in the affidavit.
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He said he panicked at that and grew angry, the affidavit alleges. But he “blocked” what happened next and when his memory returned, he was at an intersection behind the wheel of his car.
The affidavit alleges that, in his lap, was the ear piece for a pair of headphones and Rivera realized: Tibbetts was in his trunk.
He turned around and drove back into a cornfield, according to the affidavit. In his trunk he found Tibbetts’ body, with “blood on the side of her head,” he allegedly told authorities. She was still wearing her headphones.
To allegedly dispose of the body, Rivera said he next dragged and then carried Tibbetts deeper into the cornfield, the affidavit states. He “covered her in some corn leaves” and left her behind, lying face-up in the field.
With his phone, Rivera retraced how he had gotten to the field from Brooklyn and, after being questioned, was able to take law enforcement back there from memory, according to the affidavit. Tibbetts’ body was found right where he said she would be.
A police source said Tuesday that she’d been dumped in a cornfield in Guernsey, about 15 minutes by car southeast from Brooklyn.
At a news conference on Tuesday announcing Rivera’s arrest, state authorities declined to discuss a possible motive. However, they said, Rivera “seemed to be drawn to her [Tibbetts] on that particular day and chose to abduct her.”
It remains unclear when, exactly, Tibbetts was killed and how well she may have known her suspected murderer, if at all.
Rivera had allegedly seen Tibbetts before, according to Rick Rahn of the Iowa Division of Criminal Investigation, but he told reporters on Tuesday that he could not elaborate.
Rivera reportedly remains in custody in lieu of $1 million bond. It was unclear if he has retained an attorney who could comment on his behalf. He is scheduled to appear in court on Wednesday afternoon, according to the Register.
Tibbetts’ loved ones, meanwhile, are left to grieve after finally learning the truth about her disappearance.
“It’s definitely not going to be easy, not for a long, long time,” friend Alyssa King said. “But we’ve got a pretty sweet angel with us all now and we will continue to spread her love and life to everyone.”