German authorities say there are people who may have information on where the body of missing Madeleine McCann, now believed to have died, was left.
Prosecutors said on Thursday they are investigating a 43-year-old German man on suspicion of murder.
The statement came after it was revealed this week a new suspect had emerged who is serving time in Germany for a sex crime.
He has been sent to prison before for sexual abuse of children, which may not be known to many who have come into contact with him.
It is the latest development in the search for Madeleine McCann, who disappeared during a family holiday in Portugal in 2007.
The German Federal Criminal Police Office (BKA) released a statement which said 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”.
“We explicitly ask these persons to contact us and provide information.”
It is one of seven lines of inquiry that authorities have asked for help with. Here are the other six.
The suspect’s vehicles
The BKA has asked for any information on vehicles used by the suspect, and asked for anyone who saw them in May 2007 to come forward.
He used a dark coloured Jaguar XJR6, officials said. The last known time it was registered after the day Madeleine disappeared was in Augsburg.
The suspect also used a white and yellow VW T3 Westfalia, with a Portuguese registration. He did not own it. The BKA said information suggests he may have used one of these vehicles during the incident.
Anyone who also knows where these vehicles were parked when Madeleine disappeared has been asked to come forward. Authorities know the whereabouts of both vehicles.
Important phone numbers
Two phone numbers have been distributed by the BKA.
The number +351 912 730 680 was “almost certainly” used by the suspect around the time of the incident, the BKA said.
A phone call with an unidentified person was made on 3 May 2007, the day of Madeleine’s disappearance. The person on the line used the Portuguese number + 351 916 510 683.
Officials said the person who used that number “is considered an important witness” but was not staying in the area at the time the call took place.
Anyone with information on both the numbers or the people using them have been asked to come forward.
The suspect lived “more or less permanently” in the Algarve from 1995 to 2007, the BKA said. For several years, he stayed in a house between Lagos and Praia da Luz.
He worked in several jobs including the gastronomy business in the Lagos area and is believed to have also taken part in burglaries of hotels, holiday flats and drug trafficking.
Photos of places the authorities have linked the suspect to have been issued and anyone with information on them, or other points of contact, have been asked to get in touch.
Contact with people connected to the vehicles, buildings and numbers
Anyone who has come into contact with people who have links to the buildings in the photos, the vehicles and the published phone numbers have been asked to get in touch as they may have information that helps the BKA investigation.
They have been asked to provide information on where those people were in early May 2007.
Victims of the suspect
Anybody who believes they were a victim of the suspect has been asked to come forward, though no further details were provided about the suspect or potential cases.
Tourists who visited the Algarve
Police have asked anyone who visited the Algarve in early May 2007 who still have images, such as holiday photos and videos, from that time to come forward.
A €10,000 (£8,975) reward has been posted by the BKA, while £20,000 has been put up by the Metropolitan Police for information that leads to a conviction.
The Met can be emailed on email@example.com and the BKA can be contacted on +49 611 55 - 18444.