The head of the Slovak branch of a Russian motorcycle club known for its allegiance to the Kremlin has been fined a hefty amount for storing decommissioned military equipment, including a tank, on a former military base, Slovak media report.

Slovakia's Economy Ministry fined Jozef Hambalek, the founder of the Night Wolves's Slovak branch, 33,000 euros because he failed to "inform in writing about the categories, types, and numbers of decommissioned and disabled products of the defense industry that he owns, including their depositing site," the ministry's press department was quoted as saying on August 29 by the news website, Radio Free Europe / Radio Liberty (RFE/RL) said.

The fine, which Hambalek has asked to pay in installments, was imposed after a month-long audit at a former military complex in the village of Dolna Krupa, 60 kilometers northeast of Bratislava, where the Slovak chapter of the Night Wolves established its base in June.

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The facility came under the scrutiny of the Economy Ministry after Hambalek stored decommissioned heavy military equipment, including a tank, on the premises.

Members of the Night Wolves motorcycle club helped Russia occupy Ukraine's Crimea region in 2014.

The Russian group, nicknamed Putin's Angels, has also been hit with Western sanctions over its support for Russia-backed separatists in eastern Ukraine.

Last month, Slovak President Andrej Kiska said that the existence of the Dolna Krupa base where the Night Wolves operate along with a local pro-Russia paramilitary group presents a security risk for the EU and NATO country.

Hambalek, who is said to have close ties with former Interior Minister Robert Kalinak, reportedly owns the complex.