Ukrainian drones penetrated several layers of air defenses around Moscow, Kyiv said on Thursday.

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Ukrainian drones penetrated three layers of air defenses deployed to protect Moscow and attacked a major Russian oil facility, Kyiv said on Thursday, marking its latest deep-strike operation.The massive Ukrainian attack targeted the Moscow Oil Refinery, one of Russia's largest, for the second time in just a few days, and appears to be the largest strike on the capital city in several years."Despite three layers of air defense systems deployed in Moscow, as we have said before, we will still reach them," Ukrainian President Volodymyr Zelenskyy told reporters in a WhatsApp chat.In early May, he said that Russia had relocated a significant number of air defense systems to Moscow from other regions as part of a bid to better protect the city ahead of the May 9 Victory Day parade.Zelenskyy said on Thursday that if Russian President Vladimir Putin "does not want to end this war and chooses to continue it, we will not sit quietly — we will respond. The response must be strong and just.""We certainly do not want Ukraine to be burning because of the enemy," Zelenskyy said. "But if Ukraine is burning, your Moscow will be burning as well."The Ukrainian military confirmed the attack early Thursday and said the refinery, located hundreds of miles from the front lines of the war, produces more than 12 million tons of oil annually. Fuel from the facility supports Russia's economy and military logistics.