Hans Christian Wolters, a spokesman for the Braunschweig Public Prosecutor's Office, said in a statement: "We are assuming that the girl is dead".
The day after Madeleine went missing, the suspect got the auto re-registered in Germany under someone else's name, although it is believed the vehicle was still in Portugal.
Police from Britain, Germany and Portugal launched a new joint appeal for information in the case Wednesday.
The man is said to be white, with short blonde hair and about six feet tall, and had a slim build when Madeleine went missing. He had been living in a camper van in the Praia da Luz area when Madeleine and her family were vacationing and made a phone call an hour before she was abducted.
She was 4 years old at the time, and on the day of her disappearance her parents were outside the home eating with friends at a nearby tapas bar in the Praia da Luz resort.
Kate and Gerry cling onto a glimmer of hope that Maddie could still be alive as police probing her disappearance have sensationally revealed a prime suspect in a huge breakthrough in the 13-year mystery.
"There is reason to assume that there are other persons, apart from the suspect, who have concrete knowledge of the course of the crime and maybe also of the place where the body was left", German police said.
German investigators are due to give an update later, but are now classifying the investigation as a murder inquiry.
He is now serving a prison sentence for a sex crime and has two previous convictions for "sexual contact with girls".
The suspect has reportedly been sentenced to prison for child sexual abuse on numerous occasions in the past.
They also released details regarding two vehicles the suspect had access to, as well as two cell phone numbers.
His name was given to the Metropolitan Police in 2017 after the 10th anniversary of Madeleine's disappearance.
The young girl vanished from a holiday villa in Praia da Luz in Portugal 13 years ago.
According to authorities, the suspect lived periodically in the area of her disappearance from 1995 to 2007.
Both cars, a Volkswagen camper van and a Jaguar, are now in the possession of German police. They've never given up on that hope, nor will they until they are presented with any incontrovertible evidence to the contrary.
"Someone out there knows a lot more than they're letting on", DCI Mark Cranwell, leading the Met inquiry, said. "We would like to thank the police forces involved for their continued efforts in the search for Madeleine".
"All we have ever wanted is to find her, uncover the truth and bring those responsible to justice", her parents, Kate and Gerry, said in a statement issued before the German prosecutor spoke. "It was used in and around the area of Praia da Luz". "On 4 May 2007, the day after Madeleine's disappearance, the auto was re-registered to someone else in Germany".
"But they are realistic and they say that whatever the outcome of this appeal and the police work, they do need to know because they need to find peace".
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It has put safety measures in place including Perspex screens, face coverings, gloves and social distancing measures. The fast-food chain reopened a number of outlets across Preston, South Ribble and Chorley during Wednesday (June 3).
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If they test negative and their symptoms resolve, they may continue to work while monitoring themselves for 14 days. Hammel shared that the reliability of antibody tests seems to be promising at the moment, though no test is ideal .