Ukraine launched its largest drone attack on Moscow on Tuesday, with at least 91 drones targeting the Russian capital, resulting in at least two fatalities, fires, airport closures, and flight diversions, according to Russian authorities. 

Russian officials reported downing 337 Ukrainian drones, including 91 over Moscow and 126 over the Kursk region, where Ukrainian forces are withdrawing. 

The massive pre-dawn attack came as Ukrainian officials were set to meet with a US team in Saudi Arabia to explore potential peace talks in the ongoing conflict, while Russian forces encircle thousands of Ukrainian troops in Kursk.

Moscow Mayor Sergei Sobyanin stated that air defenses were still intercepting attacks on the city, which, along with its surrounding area, houses over 21 million people, making it one of Europe's largest metropolitan regions.

"The most massive attack of enemy UAVs (unmanned aerial vehicles) on Moscow has been repelled," Sobyanin said in a post on Telegram.

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Moscow Region Governor Andrei Vorobyov reported that at least one person was killed and three others injured, sharing an image of a damaged apartment with blown-out windows. He noted that some residents were evacuated from a multi-story building in the Ramenskoye district, located about 50 km southeast of the Kremlin.

Despite the attacks, Moscow showed no signs of panic, with commuters continuing their daily routines in the city center. To maintain air safety, Russia's aviation authority halted flights at all four Moscow airports, while two airports in the Yaroslavl and Nizhny Novgorod regions, to the east of Moscow, were also shut down.

Although US President Donald Trump expresses a desire for peace in Ukraine, the war intensifies on the ground with a significant Russian spring offensive in Kursk and a series of Ukrainian drone strikes deep within Russian territory.

Russia's electronic anti-drone umbrella 

Russia has deployed numerous electronic "umbrellas" over Moscow and key installations, along with advanced layers of defense around strategic buildings, creating a complex air defense system designed to intercept drones before they reach the Kremlin. 

In response, Kiev, frequently targeted by mass drone strikes from Russian forces, has retaliated with its drone attacks, targeting Russian oil refineries, airfields, and strategic early-warning radar stations.

Both Moscow and Kiev have focused on acquiring and developing new drones, employing them in innovative ways, and devising methods to destroy them, from farmers using shotguns to advanced electronic jamming systems.

Both sides have turned cheap commercial drones into deadly weapons, significantly ramping up production.

Russian President Vladimir Putin, aiming to shield Moscow from the hardships of the war, has branded Ukrainian drone attacks on civilian infrastructure, such as nuclear power plants, as "terrorism" and promised retaliation.