Ukraine has likely established a network of pro-Ukrainian sabotage agents within Russian territory to carry out strategic drone attacks, CNN reported on June 5.
According to CNN, multiple people familiar with U.S. intelligence on the matter said that pro-Ukrainian agents and "operatives well-trained in this kind of warfare" are being provided with Ukrainian-made drones.
It is likely that Ukraine used "well-practiced smuggling routes" along the Ukrainian-Russian border to send drones or drone components into Russia.
U.S. officials believe that these agents were likely responsible for the drone attack that targeted the Kremlin in early May, CNN wrote.
However, it remains unclear if they were behind other recent drone attacks, such as the one which targeted high-rise buildings in Moscow in late May.
According to sources familiar with U.S. intelligence, the frequency of drone strikes within Russian territory appears to be "a culmination of months of effort" on Ukraine's part to "set up the infrastructure for such sabotage."
Ukraine's Security Service neither confirmed nor denied their involvement when asked by CNN for comment.
U.S. and other Western officials told CNN that it was a "smart military strategy that could divert Russian resources to protecting its own territory" ahead of Ukraine's counteroffensive, despite offering conflicting public statements on attacks within Russian territory.