A reproduction of the Tsar Bomba, the biggest nuclear weapon ever detonated, at the Nuclear Weapons Museum at RFNC-VNIIEF in Sarov, where Russia designs and builds its nuclear weapons—and some engineers apparently decided to try to do some nuclear-powered blockchain mining. (credit: Croquant & Hex)

Russia’s Interfax News Agency reports that engineers at the All-Russian Research Institute of Experimental Physics (RFNC-VNIIEF)—the Russian Federation Nuclear Center facility where scientists designed the Soviet Union’s first nuclear bomb—have been arrested for mining cryptocurrency with “office computing resources,” according to a spokesperson for the Institute. “There has been an unsanctioned attempt to use computer facilities for private purposes including so-called mining,” said Tatyana Zalesskaya, head of the Institute’s press service.

Zalesskaya did not say how many people were detained, and the Federal Security Service (FSB) has not issued a statement on the arrests or criminal charges pending. But reports indicate that the group was caught trying to harness the lab’s supercomputer to mine cryptocurrency.

The Institute is located in Sarov, a “closed” city east of Moscow where nuclear weapons research has been conducted since 1946. The facility is so secret that it was left off Soviet maps; Sarov is surrounded by fences and guarded by the Russian military accordingly. While the city is the home of Russia’s Nuclear Weapons Museum, don’t plan a visit anytime soon—access to Sarov is restricted, and no one who does not live in the city is allowed to visit without permission. Foreigners visiting on official business have to surrender their passports, cell phones, and other electronic devices at the city’s checkpoints.