The FBI said Friday that Brian Laundrie left behind a notebook entry claiming "responsibility" for the death last year of fiancee Gabby Petito, a final chapter in the high-profile missing person manhunts that stretched from Utah to Florida.
"A review of the notebook revealed written statements by Mr. Laundrie claiming responsibility for Ms. Petito's death," an FBI said in a statement obtained by NBC News.
FBI Denver Special Agent in Charge Michael Schneider said, "All logical investigative steps have been concluded in this case."
The couple went on a Western trip last year, but Laundrie returned to his parents' Florida home without Petito.
Police body cam video later showed officers responding to a report the couple had been in a fight in September in Utah.
The body of Petito, a 22-year-old social media influencer, was found Sept. 19, 2021, in Wyoming, concluding a search that drew national attention. Investigators says she died by strangulation several weeks earlier.
Laundrie, who was a prime suspect in the case related to Petito's whereabouts, went missing shortly after returning to Florida. His body was found Oct. 20, 2021, in a nature preserve near his parents' home.
A search of the area also turned up a backpack, notebook and a revolver linked to Laundrie, also according to NBC News.
A Florida medical examiner ruled Laundrie died from a self-inflicted gunshot wound.