When the 18-year-old rebuffed him, van der Sloot, then 17,smashed a cinder block over Natalee’s headso that her face “collapsed in,” he said earlier this month, providing horrifying details of the teenager’slong-unsolved killing, which werereported first in PEOPLE.

“I lay her down – we lay down together – in the sand and, uh, we start kissing each other,” van der Sloot, now 36, claimed to his lawyer in the recorded confession, which was part ofa plea agreementin aconnected federal case for extortion and fraudin Alabama.

Natalee Holloway and her mother, Beth Holloway.Courtesy of Beth Twitty

Natalee Holloway,

Courtesy of Beth Twitty

Van der Sloot said when he tried to escalate the sexual encounter, “she tells me ‘no.’ She tells me she doesn’t want me to — to feel her up. Uh, I insist. I keep feeling her up either way.”

Unable to get him off of her, Natalee kneed him in the crotch, van der Sloot claimed.

AP/ Kypros/Getty

Natalee Holloway, Joran Van der Sloot

Subsequently, he said he kicked Natalee “extremely hard” in the face.

Natalee went “unconscious, possibly even uh, even dead, but definitely unconscious,” van der Sloot said.

Natalee Holloway with her dad, Dave Holloway.Courtesy of Beth Twitty

Natalee Holloway, 18, left stands with her father Dave Holloway on her graduation day from Mountain Brook High School in Mountain Brook, Alabama, Tuesday, May 24, 2005.

That’s when he noticed “a huge” cinder block lying in the sand right “right next to her,” he said, adding: “I take this and uh, yeah, I– I– I smash her head in with it completely. Uh, yeah, her face basically, you know, uh collapses in.”

Sitting in federal detention with cinderblock walls at the time of this confession, he told Kevin L. Butler, one of his federal defenders, that the cinder block he used to kill Natalee was the “exact same” as those then surrounding him. (Neither Butler nor van der Sloot’s two other lawyers responded to PEOPLE’s request for comment in time for publication.)

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“Uhm, afterwards,” van der Sloot stuttered on through his recollections of that May 30, 2005 night. “I don’t know what to do. “

He grabbed Natalee’s body and “I half, uh, half pull and half walk with her into the ocean,” he said, adding that he walked them into the water “to about my knees” and “I push her off into– into the– into the– into the sea.”

Then, “I get out. I– I walk home.”

Beth Holloway.Pablo Martinez Monsivais/AP

Beth Holloway, mother of Natalee Holloway, speaks during the opening of the Natalee Holloway Resource Center (NHRC) at the National Museum of Crime & Punishment in Washington, Tuesday, June 8, 2010

Pablo Martinez Monsivais/AP

The confession filled in the previously-unknown final hours of the life of the aspiring doctor who was celebrating her high school graduation on a class trip to Aruba and had last been seen leaving an island bar with van der Sloot earlier that day.

Thestatute of limitations for murder in Aruba is 12 years, so van der Sloot – who had previously been arrested several times in connection to Natalee’s disappearance but never charged – will likely not be prosecuted for her murder, despite confessing to her killing.

Natalee waslegally declared deadin 2012, but her body was never found.

Van der Slootpleaded guiltyWednesday to one count each of extortion and wire fraud, admitting to taking about $25,000 of Beth Holloway’s money in 2010 on the false premise of giving the grieving mother answers to her daughter’s disappearance. After supposedly directing the family to her body in exchange for the funds, van der Sloot later emailed them to say his intel was “worthless,” prosecutors say. He took off to Peru with the money that May.

Natalee Holloway’s parents, Dave and Beth Holloway, with Beth’s lawyer (center) John Q. Kelly in court Wednesday.Courtesy of John Q. Kelly

Beth and Dave Holloway with John Q. Kelly (center), Natalee Holloway case

Courtesy of John Q. Kelly

Standing outside the Birmingham, Ala., courthouse following the hearing, Beth said the answers van der Sloot finally provided gave her “the end” to “this never ending nightmare,”per WBRC.

Stephany Flores Ramírez, Joran van der Sloot and Natalee Holloway.SplashNews; Karel Navarro/AP; AP Photo/Courtesy of Beth Twitty, HO

Stephany Flores Ramirez; Joran van der Sloot; Natalee Holloway

SplashNews; Karel Navarro/AP; AP Photo/Courtesy of Beth Twitty, HO

Until this June, van der Sloot had been in a prison in Peru on a28-year murder sentencein the brutal 2010 killing ofStephany Flores Ramírez, a 21-year-old student, who, he laterreportedly told investigatorsdiscovered his identity as the person of interest in Natalee’s disappearance while sharing a hotel room together in Lima. The two fought, and van der Sloot, then 22, would later admit to beating, choking and smothering her to death — the same month he traveled to Peru with the money extorted from Natalee’s mom and exactlyfive years to the dayof Natalee’s disappearance.

Peru granted the “temporary surrender” of van der Sloot to stand trial in Alabama before returning to Peru to finish his sentence,U.S. federal prosecutors said in a statement this summer.

A federal judge sentenced him Wednesday to 20 years behind bars for the financial crimes, prosecutors said in a statement, noting that the plea agreement hinged on van der Sloot’s “full, complete, accurate, and truthful information regarding Natalee Holloway’s disappearance.”

The American sentence will run concurrently with his Peruvian one, but if officials there release him early, he will serve the remainder of the 20 years in the U.S.

“It feels victorious,” Beth said, per WBRC. “Like we finally transitioned from the victim to the victor.”

source: people.com