A collection of Dutch 17th century art stolen a decade ago was found in a villa in east Ukraine and offered for sale by a far-right militia, a museum has claimed.

The 24 paintings and silver artefacts were valued at €10m ($10.8m; £7m) when they were stolen from the Welfries Museum in Hoorn a decade ago. Two art detectives hired by the museum claim they were offered for sale for the inflated sum of €50m by a member of a far-right militia with alleged ties to a politician and former senior security official.

"But we only wanted to pay them for their expenses, since these paintings are the legal property of the museum, so it's not for them to hold or sell the paintings," said Ad Geerdink, director of the museum.

Geerdink said that the museum was making the alleged fate of the collection, which includes pieces by Jan van Goyen and Hendrick Bogaert, public as it was in danger of being sold on the black market and lost forever.

"There are very strong signs that the paintings are now being offered to other parties or have even been sold," Geerdink said. "Given the paintings' fragile condition, it is already one minute to midnight, or even one past midnight."

Art detective Alex Omhoff told IBTimes UK:"All efforts to get the paintings back were made. Dutch politicians were involved. Our foreign minister asked the Ukrainian president for help and we tried by negotiating with these people to get the art back, but unfortunately money is more important to them than historically important pieces of art."

His colleague Arthur Brand told reporters in a news conference at the museum that members of of the Ukrainian SBU secret service played a role in trying to sell the painting, NOS TV in the Netherlands reported.

The museum said in a statement: "Further research by Brand shows that other highly placed individuals are operating behind the scenes of the volunteer battalion. The stolen art is used as a pawn in a non-transparent Ukrainian political arena riddled with internal power struggles, favouritism and corruption."

In the audacious heist, thieves are believed to have hidden in an antique coffin in the museum until it closed, before disabling the alarm systems and stealing the artworks.