Anton Gerashchenko, an adviser to Ukraine's interior minister, has claimed that Russia's defence minister suffered a heart attack.
Sergei Shoigu had not been seen publicly since 11 March, until he appeared briefly in a video released by Putin on Thursday 24 March.
"Shoigu's heart attack happened after a tough accusation by Putin for a complete failure of the invasion of Ukraine," Gerashchenko wrote on Facebook, adding that he is currently "undergoing rehabilitation" in hospital.
There has been no confirmation from Russia of Shoigu's alleged health problems.
BBC
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