Ukraine launched a major drone attack against Moscow and several other Russian cities on Monday night — possibly the largest Ukrainian offensive involving unmanned aerial vehicles since the war began in 2022.

The Russian military claimed it destroyed 144 of Ukraine’s drones, but some damage and fatalities were still reported.

The governor of the Moscow region, Andrey Vorobyov, said 20 Ukrainian drones were shot down in his area, but others were able to damage apartment buildings and houses in the towns of Lyubertsy and Ramenskoye. Local media photographed fires burning in a few high-rise buildings after the drone strikes.

“A woman was killed, and three more people sustained injuries. Five residential buildings near one of those damaged have been evacuated as emergency services were handling drone debris,” Vorobyov said. If his account is accurate, it would mark the first civilian death in the Moscow region since the war began.

Russian civil and military officials said more drones were intercepted over Tula, Belgorod, Kaluga, Voronezh, Lipetsk, Oryol, and Kursk, the province Ukrainian ground forces invaded in August.

Three airports outside Moscow were shut down temporarily during the attack, causing 48 flights to be diverted. The mayor of Moscow said debris from an intercepted drone damaged a house on the edge of the city, but no other Ukrainian drones were able to reach the Russian capital.

“There is no way that nighttime strikes on residential neighborhoods can be associated with military action,” Kremlin spokesman Dmitry Peskov said on Tuesday, condemning the attack.

“The Kyiv regime continues to demonstrate its nature. They are our enemies, and we must continue the special military operation to protect ourselves from such actions,” Peskov said.

Russia has attacked Ukrainian civilian neighborhoods many times during the invasion, including attacks on the Ukrainian capital of Kyiv. Ukrainian military chief Serhiy Popko said Russia attacked Kyiv again on Monday night with a swarm of 46 drones, 38 of which Ukraine’s air force allegedly shot down.

Drone warfare has figured prominently in the Russian invasion of Ukraine, with both sides innovating offensive and defensive tactics. Drone swarms — like those both sides reportedly launched on Monday — usually cause minimal damage because the drones are easily intercepted, but Ukraine does not have permission to use U.S. and European-supplied missiles to hit targets deep in Russia, so it must employ drones for long-range attacks. Russian oil facilities are frequent targets for these drone strikes.

Ukraine’s latest innovation, spotlighted in social media videos that the Ukrainian Defense Ministry released, is the “dragon drones” — low-altitude drones that drop extremely hot payloads of thermite on their targets. 

These thermite charges, which burn at temperatures of up to 4,000 degrees Fahrenheit, have proven extremely effective at burning away soft cover to expose Russian soldiers to follow-up attacks. 

The thermite spray can also disable or kill soldiers it comes into contact with, and it can disable armored vehicles if dropped through their hatches. Outside military analysts say the value of the weapon is probably more psychological than practical.