Twelve years after the mysterious disappearance of Natalee Holloway, one man still remains the primary suspect. Joran van der Sloot, a Dutch man, was reportedly the last person to see her before the vanished in Aruba during a trip with her classmates.

Van der Sloot denied any involvement in Holloway’s disappearance but remains behind bars in Peru for a separate crime.

Eighteen-year-old Holloway, an Alabama native, went missing in 2005 during a trip to Aruba with classmates celebrating their graduation. Holloway was supposed to meet her fellow students to depart for the United States but never showed up to meet them. She was officially declared dead in 2012, but her body was never found.

GettyImages-136742312 Joran van der Sloot, shown here in Peru Jan. 11, 2011, remains the primary suspect in the disappearance of Natalee Holloway. Photo: Getty Images

Holloway was last seen getting into a car with van der Sloot and two Surinamese brothers on the last night of her trip. Van der Sloot, who was 17 at the time, was subsequently questioned but released on a lack of evidence.

But exactly five years after Holloway disappeared, van der Sloot was arrested for the murder of another young woman. He confessed to killing Stephany Flores, 21, who he met at a casino in Peru, because she was “intruding into [his] private life.” Flores reportedly found files on van der Sloot’s computer relating to Holloway, leading him to kill her. He later tried to rescind his confession but a judge ruled it would still stand.

Van der Sloot was sentenced to 28 years in prison for Flores’ murder and remained behind bars in Peru for the crime. Now 30, he was moved to a remote Peruvian prison in 2014 after allegedly threatening to murder the warden at his first prison.

While van der Sloot remained in prison, a new lead in Holloway’s disappearance emerged. Her father, Dave Holloway, appeared on NBC’s “The Today Show” to announce that an 18-month-long investigation found a new set of human remains in an undisclosed location in Aruba. The remains were sent to be tested for DNA to determine whether they belonged to Holloway. Her father was led to the remains by an informant who claimed to have intimate knowledge of Holloway’s death.

“We have a person who states he was directly involved with Jordan van der Sloot in disposing of Natalee’s remains,” Dave Holloway said Wednesday. “I thought, you know, there may be something to this.”

Officials in the United States said once van der Sloot finishes serving his sentence in Peru, they would extradite him for additional questioning about Holloway.

GettyImages-136748267 Joran van der Sloot was sentenced to prison for the death of business student Stephany Flores. Demonstrators in this photo were asking for a life sentence in Lima, Peru, Jan. 11, 2011. Photo: Getty Images