This video in English from the Netherlands says about itself:
Ukraine: give back stolen art!
6 December 2015
Valuable paintings that were stolen from the Westfries Museum in The Netherlands in 2005, have turned up on the battlefield in Ukraine. The museum calls on anybody that knows where these paintings are, to return them to their rightful owners.
This picture shows the painting Vrouw Wereld, made by Dutch painter Jacob Waben in 1622. One of 24 ancient paintings (including work by, eg Jan van Goyen) and much silver, stolen in 2005 from the Westfries Museum in the Netherlands.
This 7 December 2015 Dutch TV video is called (translated) Ukrainian secret service involved in art robbery at Westfries Museum.
UPI news agency said on this on 9 December 2015:
HOORN, Netherlands — Law enforcement officials say Ukrainian ultra-nationalists are behind the theft of dozens of paintings and silverware from a Dutch museum, which are being ransomed for nearly $55 million.
Twenty-four paintings by Dutch artists of the 17th and 18th century, and 70 pieces of antique silverware were stolen in 2005 from the Westfries Museum in Hoorn, near Amsterdam. Members of the Organization of Ukrainian Nationalists, a paramilitary group … recently presented evidence it had the cache of artworks. The group said it would return the items under conditions which included the payment of $54.9 million, the museum said in a statement.
It is alleged that Valentyn Nalyvaichenko, former Ukrainian Security Service chief, and Oleh Tyahnybok, leader of the right-wing Svoboda party in Ukraine, are implicated in the ransom demand, suggesting OUN has, museum representative Arthur Brand said, connections at “the very top political level.” …
Ukrainian Foreign Minister Pavlo Klimkin said Tuesday … he is worried the incident, prior to an April 6, 2016, [Dutch] referendum on Ukrainian association with the European Union, could “spoil our image.”
The Kyiv Post in Ukraine writes today about this:
Brand’s account is that two OUN battalion members initially asked €50 million for the paintings and later a €5 million finder’s fee,” according to the Dutch news release.
The detective told the Kyiv Post that he never saw the actual paintings in Ukraine, but claimed that [OUN senior officer] Humenyuk showed him photos of the entire stolen collection.
Guzhva of the OUN battalion said that Humenyuk was discharged from the battalion in March – before he approached the Dutch Embassy – after being suspected of theft and misuse of power.
“We didn’t find enough evidence to take to court, so we decided to fire him. We know Borys as a wealthy man, who was connected to the art market before the war,” Guzhva said.
Humenyuk currently serves in the Azov Battalion and is stationed near Donetsk, he said.
Brand said that Humenyuk is not the one to blame for any blackmail attempt, but was merely the contact person during negotiations.
“Svoboda Party leader Oleh Tyahnybok is the one to blame for the shocking blackmail. From my sources, I know that he’s even trying to sell the paintings to top European gangs. That is the final and the only truth,” Brand said.
Translated from Business News Radio in the Netherlands, 9 December 2015:
The Minister of Foreign Affairs of Ukraine made the criticism [of the Westfries Museum] earlier at a press conference. Supposedly, local authorities had not been asked sufficiently to help. But according to the negotiator of the museum and specialist in art crime Arthur Brand they several times tried to contact the authorities. So, according to him, it is nonsense what the Ukrainian minister says. …
The Ukrainian embassy [in the Netherlands] says it is not even certain that the paintings are in their country. But that is nonsense as well, Brand says. “It is absolutely 100 percent sure that these paintings are in Ukraine. There is not any doubt about it.”
Bloomberg news agency writes about this on 9 December 2015:
It’s not easy for [the government in] Kiev to do anything, though. Ukraine is now a country full of weapons, and these guns are in the hands of radical groups that don’t have much respect for authority. The government is careful about cracking down on the nationalist volunteers: They were instrumental in overthrowing [former president] Yanukovych, and they could be dangerous if provoked.