KYIV, Ukraine (AP) — Russia’s sustained bombardment of Ukraine’s power grid is deepening concerns about the safety of the country’s nuclear facilities after a drone knocked out power for more than three hours to the site of the 1986 Chernobyl nuclear disaster and as Europe’s biggest atomic power plant remains disconnected from the grid , officials said.

Both Chernobyl and the Russian-occupied Zaporizhzhia Nuclear Power Plant are not working but they require a constant power supply to run crucial cooling systems for spent fuel rods in order to avoid a potential nuclear incident.

A blackout could also blind the radiation monitoring systems, installed to boost security at Chernobyl and operated by the U.N. nuclear watchdog, the International Atomic Energy Agency.

“Russia is deliberately cr

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