In an interview with Portuguese TV channel CMTV on Tuesday, Wolters said detectives believed they had found "some facts, some new evidence" adding: "We are sure that he (Brueckner) is the murderer of Madeleine McCann."
Convicted child abuser and drug trader Christian Brueckner, who is behind bars in Germany for raping a woman in the same area of the Algarve region of Portugal from where Madeleine went missing in 2007 when she was three years old, was formally identified as an official suspect last month.
That was the first time a Portuguese prosecutor had identified a suspect in the case since Kate and Gerry McCann, Madeleine's parents, were named suspects in 2007.
They were later cleared.
Brueckner, 45, has denied involvement in the disappearance of Madeleine from her bedroom during a family holiday.
There has been speculation that evidence linked to Madeleine was found in the camper van Brueckner had used at the time of her disappearance.
The CMTV journalist asked Wolters if he denied those claims and he responded: "I don't want to deny it."
The camper van has been in the possession of German police since June 2020, when authorities started to seek information on Brueckner.
Wolters, who was not immediately available for comment, said he could not provide details of the ongoing German investigation because the suspect was yet to be informed.
He has previously told Reuters that the naming of Brueckner as a suspect in the case by the Portuguese prosecutor was designed to interrupt Portugal's 15-year statute of limitations.
"Regardless of outcome, Madeleine will always be our daughter and a truly horrific crime has been committed," Madeleine's parents said in a statement on Tuesday, which marked 15 years since her disappearance.
The McCanns have campaigned tirelessly to draw attention to their daughter's disappearance, and British public figures from business tycoons to authors and football stars have made appeals for information.
