German prosecutors said Friday they are investigating if the man they suspect of murdering British girl Madeleine McCann might also be linked to the disappearance of another child in Germany.

Police raised hopes this week that the decade-long mystery over three-year-old "Maddie" could finally be solved when they revealed they are investigating a 43-year-old German man over her disappearance from the Portuguese holiday resort of Praia da Luz in 2007.

The suspect, named as Christian B. by German media, has a history of previous sex offences including child abuse and rape.

Prosecutors are now examining if the man could be linked to the disappearance of a five-year-old girl named Inga from the town of Schoenebeck in Saxony-Anhalt in 2015.

Aerial and ground images show the Portugal house where the suspect in the Madeleine McCann case lived at the time of her disappearance
Aerial and ground images show the Portugal house where the suspect in the Madeleine McCann case lived at the time of her disappearance AFPTV / Carlos COSTA

"It is now being examined whether there are new leads in connection with the murder suspect in Brunswick," a spokeswoman for the Stendal public prosecutor's office told the local Volksstimme newspaper.

Inga disappeared without a trace in the woods while on an outing with her family.

According to the Volksstimme, the suspect owned a property in the region where Inga disappeared and was in the area around the period when she went missing.

A lawyer for the parents of missing British girl Madeleine McCann said a new German enquiry seemed to be "more solid" than others in the past
A lawyer for the parents of missing British girl Madeleine McCann said a new German enquiry seemed to be "more solid" than others in the past AFP / FRANCISCO LEONG

Madeleine went missing from her family's holiday apartment on May 3, 2007, a few days before her fourth birthday, as her parents dined with friends at a nearby tapas bar.

Her disappearance sparked one of the biggest searches of its kind in recent years.

Despite a wide range of suspects and theories about what happened, no one has ever been convicted over her kidnapping and no trace of her has been found.

The McCann family's Portuguese lawyer told AFP on Friday that the new line of enquiry was "encouraging" as it seemed to be "more solid" than others in the past.

Missing British child Madeleine McCann has been the subject of a huge search but no trace of her has been found so far
Missing British child Madeleine McCann has been the subject of a huge search but no trace of her has been found so far AFP / ANDREW YATES

"There has been mistrust on the part of the parents with regard to the information that came out and promised a conclusion to the case. This time, it is inevitable that it represents a glimmer of hope," Rogerio Alves said.

But in Praia da Luz, there was scepticism among residents over the latest lead.

"We've seen other news like that but the case has remained a mystery," said Miguel Domingues behind the counter of a shop that he runs at the seaside village in the Algarve region.

A British resident in the village, who spoke on condition of anonymity said: "We're fed up. This gets racked up every year. It's a shame."

Launching an appeal for information on the suspect on Tuesday, German police have said they are working on the assumption that Madeleine is dead.

According to police, the suspect, a white man with short blond hair, lived in the Algarve region of Portugal between 1995 and 2007.

He made a living doing odd jobs in the area where Madeleine disappeared, and also burgled hotel rooms and holiday flats.

The German suspect is currently serving a prison sentence for drug trafficking but is close to a decision on possible release on probation as he has completed two-thirds of his time, according to documents from Germany's Federal Court of Justice (BGH) seen by AFP.

Citing official investigation documents, Spiegel magazine on Friday published chilling extracts of a chat between the suspect and a friend in 2013.

Christian B. told an acquaintance he wanted to "capture something small and use it for days on end", the report said.

In response to the suggestion that this was dangerous, he then allegedly replied: "Oh, if the evidence -- afterwards -- is destroyed."