Ukrainian drones appear to be getting better at bypassing Russian air defenses to strike critical infrastructure.

After Ukrainian drones hit locations across Moscow on June 18 — the largest attack since the start of Russia's full-scale invasion of Ukraine — a debate was sparked about holes in the country's defense net.

A major oil refinery in Moscow, which supplies 40% of the region's fuel, was set alight and production appeared to have halted for several days after the attack. There were also evacuations at Russia's largest airport. Eyewitnesses flooded social media with footage of what looked like failed air defense interceptions of the drones.

"That impression forms among non-specialists, who see a missile fly past a drone without hitting it ," Ruslan Leviev, a Russian dissident, military analyst and founder of the investigative group Conflict Intelligence Team, told DW.

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