Moscow came under a major drone attack overnight, the city’s mayor said Tuesday, less than two weeks after Ukraine launched a large-scale drone assault on the Russian capital.

Mayor Sergei Sobyanin reported several waves of drones, starting Monday night. He said on Telegram that Russian air defenses had shot down more than 60 drones, and that emergency services were working at crash sites. He did not mention any injuries.

Mr. Sobyanin did not say where the drones had come from, and there was no immediate public comment from the authorities in Ukraine.

Russia’s federal aviation watchdog on Tuesday morning briefly issued emergency restrictions at major airports serving Moscow, citing flight safety reasons.

The agency, Rosaviatsiya, said on Telegram that Moscow Domodedovo Airport and Zhukovsky International Airport had been reopened less than two hours after the restrictions were announced.

Earlier this month, Ukraine launched one of its largest drone attacks against Moscow. The attack, which injured at least 17 people in the Moscow region, targeted a major oil refinery and forced the temporary closure of the city’s four airports. The Russian Defense Ministry later said it had downed almost 1,000 drones across the country during the attack.

President Volodymyr Zelensky of Ukraine said that attack was a response to a strike on a monastery complex in Kyiv. Russia claimed that it had been hit by an errant Ukrainian interceptor missile.

This is a developing story.