German police are investigating whether the suspect in Madeleine McCann’s disappearance is behind the gruesome murder of a young schoolgirl 24 years ago.
Claudia Ruf was only 11 when police say she was abducted while walking her neighbour’s dog in the town of Grevenbroich, near Cologne and Dusseldorf, in May 1996.
Her killer raped and strangled her before dousing her body in petrol and setting it on fire.
Her remains were found more than 40 miles away, near Bonn, two days after she disappeared.
In the years since then police have pursued a number of leads and carried out mass DNA testing on around 1,000 men, but have never charged a suspect.
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After paedophile Christian Brueckner, 43, was identified as the new prime suspect in the McCann case, German police began taking another look at the Ruf case to find out if he was involved, Bild reported.
A spokesman for Bonn police said it was a “routine process”.
Police forces across Europe are currently reviewing unsolved disappearances or murders of children, and rapes of women to find out if there is a connection to the McCann suspect.
In the Ruf case, police announced last year they had sent letters to at least 900 men inviting them to voluntarily provide a DNA sample as part of efforts to identify a potential killer and rule out local residents from the suspect pool.
Last November, the first saliva swab tests were taken from men who were aged between 14 and 70 at the time of Claudia’s disappearance and lived nearby.
Almost 500 men gave samples on the first day.
The results were expected in four to eight weeks.
More than six months on, no one has been charged.
An earlier mass testing campaign, which analysed the DNA of about 350 men in 2010, was unsuccessful.
Police said last year’s testing was based on new clues, and they suspect the killer had close ties to the town.
Murder detective Reinhold Jordan, of Bonn police, said officers suspected the offender used a cellar, garage or shed to carry out the crime.
Officers received dozens of new tips as part of the renewed effort to solve the crime.
In November, Claudia’s father begged members of the public to help police to catch his daughter’s killer.
He said in a video posted online: “After more than 23 years, there’s a big opportunity to solve the sad fate of my daughter.
“The perpetrator has, for too long, been able to hide behind us all.”
German prosecutors suspect Brueckner abducted and murdered three-year-old Madeleine from her family’s holiday apartment in Praia da Luz on the night of May 3, 2007.
The paedophile was living nearby at the time and was travelling around the Algarve in a VW camper van, according to investigators.
He has twice been convicted in Germany of sexually abusing a child.
He is serving a 15-month prison sentence in Kiel for drug dealing and could be freed as early as July 17 if the European Court of Justice overturns his conviction for the rape of the 72-year-old American woman in Portugal.
Brueckner is appealing his conviction for the September 2005 attack on the woman, also at Praia da Luz, for which he was sentenced to seven years in jail.
His lawyers are appealing, claiming that German police broke law by extraditing him from Portugal on a drugs charge but then putting him on trial for rape.
He was previously investigated after five-year-old Inga Gehricke, dubbed the “German Maddie”, vanished in May 2015 during a family picnic near Stendal, but there was no evidence linking him to the girl’s disappearance and he wasn’t charged.
Police were reviewing that case this month, among others.
Less than a year after Inga disappeared in a forest, police raided a disused factory site near Braunschweig and seized a red and white Tiffin Allegro Bay motorhome he bought in Germany in 2010, three years after Maddie’s disappearance.
A new TV documentary claimed girls’ swimming costumes, children’s clothes and 8,000 child abuse images were found by police. Brueckner does not have any children.
He also allegedly boasted a motorhome he owned and drove repeatedly between Germany and Portugal was ideal for hiding “drugs and children”.
Brueckner has told his lawyer that he wasn’t involved in the McCann disappearance. The suspect, currently in jail in Kiel in northern Germany, has refused to speak to detectives.
Germany’s Spiegel TV has claimed in a documentary that police seized the motorhome in May 2016, as part of an investigation into the disappearance of five-year-old Inga Gehricke – the so-called German Maddie.
During a six-day examination of the site, police found girls’ swimming costumes’, children’s clothing and computer memory sticks with more than 8,000 files, mostly containing pictures and videos of child abuse, the documentary said.
It alleged some of the victims in the images were infants and about 100 of the files were photos of Brueckner partly naked or wearing black stockings and committing a sex act.
The items were in a carrier bag buried beneath the body of Brueckner’s dog.
Brueckner was charged in relation to the child pornography, but not in relation to Inga.
A friend of Brueckner’s, identified in the documentary as Bjorn R, spoke of Brueckner’s behaviour while he lived near holiday resorts in Portugal.
“Alcohol sometimes loosened his tongue. He said that he was in Portugal and he got in everywhere and stole cameras,” Bjorn R said.
A former ambulance driver who met Brueckner and saw the RV alleged: “He told me, ‘I can transport children, kids, in this space. Drugs and children, you can transport them in this van, it’s a safe space in the van, nobody can find them. Nobody can catch you’.”
While living in Braunschweig, Brueckner ran a kiosk between 2013 and 2015.
Bjorn R told the documentary he had been contacted in 2013 by police investigating Madeleine’s disappearance.
He said: “One day I came into the kiosk and he was a little bit distraught and said, ‘Hey, look what I’ve got here’ – and he showed me a subpoena for the Madeleine McCann case.
“You could see it churned him up a bit but he wasn’t panicking and he wasn’t saying ‘they are on my heels’.
“I think he said he had been there but that he had nothing to do with it and that was that.”
Brueckner has racked up 17 convictions across Europe, including for sex offences against children, drug offences, theft and forgery.
It emerged this week that Brueckner is also under investigation for the brutal rape and murder of 13-year-old Tristan Brubach in Frankfurt.
The boy’s throat had been slashed and his body mutilated, with his testicles and flesh from his buttocks and thighs cut off.
The body parts have never been found.
Tristan’s body was found in an underpass near the Frankfurt-Hochst train station after he was killed.