Madeleine McCann, 3, went missing in 2007. No one has ever been charged in her disappearance

German police allege they discovered disturbing messages and writings on a  hard drive at Christian Brueckner’s home during a 2016 search, including a “horrifying” Skype chat in which the suspected kidnapper of Madeleine McCann allegedly wrote he wanted to “capture something small and use it for days,” according to a new report.

The “disturbing” evidence, according to a report this week by The Sun, also includes writings allegedly authored by Brueckner, now 48, describing fantasies about drugging a young girl and her mother outside of a preschool before abusing the child. German investigators also allegedly discovered 75 swimsuits for adolescent girls and photographs depicting child abuse.

The hard drive also included information that reportedly led police to believe Madeleine is dead, according to The Sun report, which aired this week on the Channel 4 network. Madeleine, who went missing in 2007, has never been found. German police have said Brueckner, who is currently in prison on an unrelated rape conviction, is the primary suspect.

Madeleine McCann and Christian Brueckner.Collect/Handout / Alamy Stock Photo, Carabinieri via AP

According to the newspaper, the newly revealed evidence came from a 2016 search at Brueckner’s home, which resulted in authorities discovering the hard drive underneath his buried dog.

PEOPLE recently looked back at the 2007 abduction of Madeleine. No one has ever been charged in the 3-year-old British girl’s disappearance.

What Happened to Madeleine McCann? A Complete Timeline of Her Disappearance

Madeleine, who would’ve turned 22 next week, is believed to have been taken from her family’s vacation apartment in Praia da Luz, Portugal, on May 3, 2007. Madeleine was just days shy of celebrating her 4th birthday at the time of her disappearance, and had been left alone at the family’s vacation apartment with her twin 2-year-old siblings while their parents Kate and Gerry McCann dined at a nearby restaurant.

Madeleine McCann.Handout/Getty

The McCanns were initially considered suspects in their daughter’s disappearance after forensic tests revealed traces of Madeleine’s blood in a car they rented 25 days after her disappearance. However, more than a decade later, police zeroed in on Brueckner and named him a primary suspect in the case.

German authorities previously said they have evidence that connects Brueckner to Madeleine’s case.

Braunschweig Public Prosecutor’s Office prosecutor Hans Christian Wolters, who was leading the investigation into Brueckner, said during a 2020 CNN interview that authorities “actually have findings that suggest that he is Madeleine McCann’s murderer.” However, Wolters lamented that investigators had “insufficient evidence to convict” Brueckner of Madeleine’s kidnapping and murder. By 2022, German and Portuguese authorities announced they had an “official” suspect but did not clarify whether it was Brueckner.

Now, the new Sun investigative report says that authorities have continued searching Brueckner’s property for clues, discovering his deceased dog, and a wallet containing six USB sticks and two memory cards buried underneath the animal.

One hard drive was described by police as “deeply concerning,” according to the Times of London.

Kate and Gerry McCann pose with an artist’s impression of how their daughter might look now at the age of nine on May 2, 2012.LEON NEAL/AFP/Getty

Brueckner has a history of sexual abuse, including against children, PEOPLE previously reported. The German national had first been charged with committing sexual offenses against children in 1993 and was later extradited from Portugal to Germany in 2017, where he spent 17 months in prison for sexually abusing a child.

He later was sentenced to seven years in prison for raping a 72-year-old woman in 2005. He is expected to be released from prison in September 2025.