(NEW YORK) — In a surprise move, a Mexican national charged with murdering Mollie Tibbetts testified Wednesday — and claimed two masked and armed men kidnapped him from his home, forced him to drive to where the 20-year-old University of Iowa student was jogging, killed her and put her body in the trunk of his car.

Cristhian Bahena Rivera, 26, took the witness stand in his own murder trial in a Davenport, Iowa, courtroom, and detailed the never-before-heard scenario of the 2018 slaying that sent shockwaves across the nation.

Bahena Rivera testified that on July 18, 2018, the day Tibbetts went missing, he emerged from taking a shower at the trailer where he lived and found two strangers in his living room.

“They were both wearing sweaters and their faces (were) covered,” Bahena Rivera said through a Spanish interpreter. “One of them was bigger and a little bit fatter. The other one was about my size.”

He testified that the larger man had a gun and the other had a knife.

“They said I should not do anything stupid and everything was going to be OK,” Bahena Rivera testified.

He said the men whispered to each other for a “long while” and then ordered him to go with them to his car, a black Chevrolet Malibu.

Bahena Rivera said the bigger man got in the backseat and the smaller man sat next to him in the front. He claimed they ordered him to drive into the nearby town of Brooklyn, Iowa.

“They told me to drive straight. One of them said to the other one about someone running,” Bahena Rivera testified.

He said they drove through town and out to rural 385th Avenue, where they “saw a person jogging.” He said he now realizes the jogger was Tibbetts.

“We just continued driving and then they asked me to turn around,” Bahena Rivera said.

He said that as they drove, the two assailants crouched down in their seats as if they didn’t want to be seen.

Bahena Rivera claimed he drove past Tibbetts three or four times. He said the last time they drove past her she was jogging in the opposite direction back into town.

“We continued forward and they asked me to turn and go back,” he said.

He said before they reached Tibbetts, he was ordered to stop, and the smaller man got out of the car and headed in the direction of Tibbetts. He claimed the other man remained in the back seat and they waited for 10 to 12 minutes.

Bahena Rivera claimed that as they waited, he heard the man in the back seat whispering to himself.

“What I heard him say was, ‘Come on Jack,"” Bahena Rivera testified.

The testimony came a day after the defense called Jack Dalton, Tibbetts’ boyfriend who had initially testified for the prosecution, back to the witness stand. Dalton had admitted he had an affair with a woman and that Tibbetts had found out and threatened to leave him about a month before her death. He testified that he was working out of town in Dubuque, Iowa, on a construction project the day Tibbetts went missing and that he had nothing to do with her death.

Bahena Rivera testified that he did not know Dalton and that he wasn’t referring to him as the one the assailant was talking about.

He testified that the smaller man returned to the car and asked him to drive forward about 300 meters, or 1,000 feet. He said they stopped again and the smaller man asked him to shut the car off and give him the keys.

He said the man got out and he heard his trunk open.

“I just heard a movement in the car and the trunk close,” Bahena Rivera testified.

He said the smaller man got back in the car and ordered him to drive straight. He claimed they drove several miles at a high rate of speed.

Bahena Rivera testified that they drove to a white house next to a cornfield, and that he was ordered to drive down a dirt road alongside the cornfield and stop.

He said the men took his keys and cellphone, and then threaten to harm his ex-girlfriend, Iris Gamboa, the mother of his 5-year-old daughter, Paulina.

“One of them tells me not to say anything about what happened, that they knew Iris and that they knew my daughter,” Bahena Rivera said. “That if I said something that they would take care of them.”

He said the two men left him alone in the cornfield, walked back to the road and vanished. He said he has never seen them since.

“I got out of the car,” he testified. “I obviously knew there was something in the trunk.”

He said he looked in the trunk and found the body of a woman he now recognizes as Tibbetts.

“At the beginning, I saw a little bit of movement. Then there was no movement,” he testified.

Bahena Rivera claimed he thought for a few minutes before he removed Tibbetts’ body from the trunk.

“I picked her up and then I put her in the cornfield,” he testified.

Under direct questioning from defense attorney Jennifer Frese, Bahena Rivera said he put leaves over Tibbetts’ body not to conceal her, but to prevent her from “being exposed to the sun.”

He said he was “scared” to call the police and feared the two men would make good on their promise to harm his family.

Bahena Rivera testified he found his keys and cellphone in the trunk of his car along with Tibbetts’ phone, Fitbit and earbuds. He said he left Tibbetts’ property on the side of a road as he drove home.

Bahena Rivera largely contradicted testimony from investigators who testified that he confessed to seeing Tibbetts running, stopped his car and ran after her. Investigators said Bahena Rivera claimed Tibbetts threatened to call the police on him and that he got angry and they fought.

Investigators said Bahena Rivera claimed he “blacked out” and didn’t remember how Tibbetts, who was stabbed repeatedly, ended up in his trunk. Bahena Rivera, according to investigators, allegedly claimed he drove Tibbetts to the cornfield and ditched her body on his own.

Prosecutors are expected to cross-examine Rivera on Wednesday afternoon.

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