Vladimir Putin’s government has launched an aggressive campaign to nationalize the assets of Konstantin Strukov, one of Russia’s richest men and the owner of the country’s largest gold mining company. The move marks a sharp escalation in the Kremlin’s efforts to extract wealth from within its own elite as the financial toll of the war in Ukraine deepens.

Strukov, whose fortune is estimated at over $3.5 billion, is the founder of Yuzhuralzoloto—a gold empire built over decades with strong ties to the Kremlin. But on July 5, his private jet was grounded by Russian authorities as it prepared to leave for Turkey. His passport was reportedly seized, and the aircraft barred from departing.