Putin sacked the FSB and put the secretive GRU spy agency in charge of Ukraine intelligence after a string of failures, top Russian journalists say

• Putin put the GRU spy agency in charge of Ukraine intelligence, replacing the FSB, Russian investigative reporters say.

• The head of the FSB was reportedly jailed in March following Russia's botched start to the Ukraine invasion.

• It follows multiple reports that said Putin purged multiple FSB agents over poor Ukraine intelligence.

President Vladimir Putin f…