Brian Laundrie was the only person "directly involved" in Gabby Petito's death last year, according to the FBI.
In fact, the FBI said in a press release on Jan. 21 that 23-year-old Laundrie admitted to killing his fiancée in a written confession in his notebook.
The news was part of FBI Denver's final update regarding the death of the 22-year-old YouTuber, whose body was discovered in Wyoming's Bridger-Teton National Forest in September. Authorities said that the investigation "did not identify any other individuals other than Brian Laundrie directly involved in the tragic death of Gabby Petito."
After returning home to Florida in September from a cross-country road trip without Petito, Laundrie was labeled a person of interest, but never a suspect. Five days after the FBI opened its investigation, amid increasing questions as to what happened and how Petito died, Laundrie also went missing. In October, authorities found his body, in an area previously underwater in the Myakkahatchee Creek Environmental Park. The Medical Examiner's Office later revealed that he died of a self-inflicted gunshot wound. Near his remains was a backpack, notebook and a revolver, per the FBI.
The agency said, "A review of the notebook revealed written statements by Mr. Laundrie claiming responsibility for Ms. Petito's death."
The FBI's investigation also concluded that Laundrie used tactics to attempt to "deceive" police.
"After Ms. Petito's death, there were several text messages identified between Mr. Laundrie's telephone and Ms. Petito's telephone," per the press release. "The timing and content of these messages are indicative of Mr. Laundrie attempting to deceive law enforcement by giving the impression that Ms. Petito was still alive."
Additionally, per the FBI, Laundrie allegedly used Petito's debit card "without authorization" between Aug. 30 and Sept. 1, while driving back to Florida from Wyoming.
In November, the Teton County Coroner's Office concluded that she was killed with "blunt-force injuries to the head and neck, with manual strangulation." The FBI said the investigation "quickly focused on the last person believed to see her alive—Mr. Laundrie."
An investigator has since determined that Moab Police in Utah made "several unintentional mistakes" when they had previously stopped and spoken to Laundrie and Petito in August following a domestic violence allegation.
At the conclusion of the investigation on Friday, Jan. 21, the Petito family issued a statement through their attorney. "We truly appreciate the FBI's diligent and painstaking efforts in this extremely complicated case," they said. "The quality and quantity of the facts and information collected by the FBI leave no doubt [that] Brian Laundrie murdered Gabby."