The photograph of the man who may have helped save his siblings and father from captivity has been released.
Jan Zon van Dorsten, 25, raised the alarm that he and his family were being kept in a ‘small, enclosed space’ in an isolated farmhouse in Ruinerwold, 60 miles north of Amsterdam in the Netherlands.
He went into a local bar and cafe on Sunday evening, ordered five beers and told the owner he had not been outside for nine years.
Police said five adult children and their father were being kept on the remote farm after Jan came forward, sparking an investigation.
According to local media reports, the family were being locked away, ‘waiting for the end of time’.
The five siblings, aged between 18 and 25, were found along with their sick father in a secret room on the farm, police said. All six people rescued are now receiving medical treatment.
In a statement, investigators said: ‘We found six people living in a small space in the house which could be locked, not a cellar. ‘It is unclear if they resided there voluntarily.
They say they are a family, a father and five children.’ A seventh man, 58, was arrested following the discovery of the family on Tuesday, but is not the father of the children, local Mayor Roger de Groot said. His role is still unclear.
The Dutch newspaper Algemeen Dagblad daily identified the man who has been arrested as Joseph B, an Austrian carpenter.
Jan was identified through social media accounts which he began posting photos to in June this year.
On his public profile on Facebook it shows he used the platform for several years until 2010, when he posted saying that he had moved to Ruinerwold.
He no longer posted on the site until June this year, when he announced he was working as an online store manager at Creconat, located in Meppel, around four miles away.
According to De Telegraaf, Creconat is associated with a timber company called Native Creative Economy, also based in Meppel, which is owned by Josef B.
A few days before he raised the alarm, Jan posted a pictures of landmarks around Ruinerwold in the dark to Facebook.
It is thought these were taken while he was walking to the bar. Bar owner Chris Westerbeek – who called police – told Dutch broadcaster RTV Drenthe Jan had been in three times but on his last visit told him he could not go home.
Chris said: ‘You could see he had no idea where he was or what he was doing. He said he had run away and that he urgently needed help.’
Investigators admit they are deeply puzzled by the case and are still working to answer key questions.
Mayor de Groot told reporters yesterday: ‘I understand there are a lot of questions. We have many too. The police are investigating all possible scenarios.’
The landlord of the farm who rented it to Josef B, Alida ten Oever, said the tenant always paid rent on time and that she never saw signs of other people living at the property.
Neighbours told RTV Drenthe that Josef was a private man who never allowed visitors inside the house, which was set back 200 yards from the nearest road and another 100 yards from the nearest building.