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According to the Wall Street Journal, today’s large-scale drone attack by Ukraine against airbases across Russia, dubbed Operation Spiderweb, which is claimed to have destroyed over 40 long-range strategic bombers and other military aircraft, took over a year and a half to prepare by the Ukrainian Security Service (SBU).
Ukrainian intelligence officials said the SBU smuggled dozens of small quadcopter drones into Russia, before then moving wooden containers into the country, which were used to hide the drones ahead of the operation against the Russian Air Force. When it came time to strike, the containers were placed on trucks and driven to locations close to each airbase, then the lids of the containers were opened remotely and the swarm of drones flew out to find their targets, most of which were Tu-95MS or Tu-22M3 Long-Range Strategic Bombers.