Russia's Federal Security Service (FSB) blocked an attempt by Ukraine to organise the hijacking of a Russian Tu-22M3 strategic bomber and fly it to Ukraine, the FSB said on Monday.
"Ukrainian intelligence intended to recruit a Russian military pilot for a monetary reward and the provision of Italian citizenship, to persuade him to fly and land a missile carrier in Ukraine," the FSB, the main successor to the Soviet-era KGB, said on its website.
Reuters could not independently verify the details. Ukraine's Security Service (SBU) has not immediately responded to Reuters' request for a comment.
During the operation, Russia received information that helped its forces to strike the Ozerne airfield in northwestern Ukraine, the FSB added in its statement.
The timings of the operation and the alleged strikes on the Ozerne airfield in Ukraine's Zhytomyr were both unclear.
The Zhytomyr region was under air raid alerts in the early hours on Monday. Unofficial reports on social media, including on the Telegram messaging app which is heavily used by officials and military in both countries for disseminating information, said there were explosions in Zhytomyr.
Reuters could not verify those reports.

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