The searches are expected to take place for several days, mostly in the land near the reservoir, Portuguese broadcaster SIC reports.

The broadcaster speculates that the search may seek to find potential evidence such as clothing given that any biological evidence is likely to have already disappeared.

The below map shows the location of the Arade dam, where investigators are expected to conduct a major search related to the disappearance of Madeleine McCann in 2007.

Christian Brueckner is believed to have called the reservoir his “little slice of paradise”, Portuguese broadcaster SIC reports.

The reservoir sits 50km from Praia de Luz, where Madeleine McCann went missing in May 2007.

Brueckner, who is serving jail time for raping an American pensioner in the same resort two years prior, is believed to have visited the reservoir on multiple occasions.

Here are some images from close to the reservoir where authorities probing the disappearance of Madeleine McCann are expected to search.

A source said that the new search in Portugal is to be led by German investigators and is linked to information they have gleaned which suggests sole suspect Christian Brueckner made regular trips to the dam, reports Gerard Couzens.

The insider said: “Portuguese police will offer logistical support but the initiative is German and they were the ones that requested the work that is going to take place this week.

“Scotland Yard officers are due to travel to Portugal but theirs will be a watching brief.”

The McCanns are expected to be kept informed of any developments as a result of the new search through Scotland Yard liaison officers.

German police would not officially confirm the search at the Arade dam – some 50km from Praia da Luz – but indicated that reports of the investigation are correct, according to the BBC.

They are expected to release a statement on Tuesday, the broadcaster reported.

The new search in Portugal comes just 10 days after Madeleine McCann’s parents shared a message for their lost child on her 20th birthday.

On the Facebook page Find Madeleine Campaign, they wrote: “Happy birthday Madeleine! We love you and we’re waiting for you. We’re never going to give up.”

The Leicestershire couple have continued to campaign despite more than 15 years passing since she went missing aged three in Praia da Luz, and they shared the message alongside a picture of Madeleine.

My colleague William Mata has more in this report:

German police looking for Madeleine McCann will begin a major search of a remote Algarve reservoir suspect Christian Brueckner used to visit.

A peninsula just over a mile long jutting into the reservoir was sealed off just after midday on Monday. Several local council lorries were spotted on the piece of land as tents and other structures were erected.

Behind them in another area just under a mile away Portuguese Civil Protection workers were seen setting up a large blue tent alongside police who had erected their own blue tent.

An onlooker said: “There are around two dozen Policia Judiciaria officers who seem to be supervising things at this stage.”

Read the full report here: