Police in the Netherlands have begun an investigation into money laundering after a substantial quantity of cash was discovered at a remote farm where a family was found hidden earlier this week.

A second man was arrested late on Thursday and was described by police as 67 years of age and the father of the group of young adults, aged between 18 and 25, who were taken into care when the house near the village of Ruinerwold, in the rural province of Drenthe, was raided on Tuesday.

In a series of tweets on Friday, police said the 67-year-old was suspected of being “a co-perpetrator” in the charges of “unlawful deprivation of liberty” and “abuse” already brought against a 58-year-old man who was found at the house and initially thought to have been the father of the group.

The 58-year-old man was remanded in custody on Thursday while police, social services and psychologists try to get to the bottom of the mystery - which burst into the open when a dishevelled 25-year-old man walked into a local bar last weekend and said he hadn’t been outside in nine years.

The 58-year-old, identified locally as “Josef B. ” and believed to be an Austrian national, is understood to be the tenant of the farm, which he personally rented from a local landowner.

Money

The money laundering charge has only been laid against the 67-year-old man, and is believed to be based on the discovery of “a large quantity of money” when police returned to carry out a fingertip search of the farm on Thursday.

Police had established early on that the mother of the young adults had apparently died, perhaps as long as nine years ago when they moved to the farm from the town of Zwarthuis, about 15 minutes away, and they were wary she might have been buried in the grounds.

Rather than human remains, however, the search yielded an unspecified amount of money, deliberately hidden, although none of those associated with the farm appears to have any visible means of support in terms of a job or social welfare.

One possible source of the money being speculated upon on Friday was that it came from the Unification Church, otherwise known as “The Moonies”, which had links to the group.

Wim Koetsier, general-secretary of the movement in the Netherlands, appeared on Dutch TV on Thursday evening and confirmed that the 67-year-old father of the group had been a member in the 1980s, but had severed his connection and disappeared.

He said the 67-year-old’s brother had also been, and remained, a member - and as a result of that parting of ways, the brothers had not been in contact since 1987.

He said the connection with the Unification Church did not explain why the group had been hidden from the world.

It was not usual for Moonies to isolate themselves, said Mr Koetsier. Their mission was to proselytise.