A drone attack in Moscow has caused minor damage to several buildings, officials say.
The capital city's mayor, Sergei Sobyanin, says there have been no serious injuries. Emergency services were "at the scene of incidents", he said.
Air defences had shot down several drones as they approached the Russian capital, officials said.
It is not immediately clear where the drones had come from.
There has been no comment from Kyiv, but on Monday, the head of Ukraine's military intelligence, Gen Kyrylo Budanov, warned of a swift response to a series of Russian missile strikes on Kyiv.
Images posted on social media showed traces of smoke in the sky above the Russian capital. Others showed a broken window.
Mr Sobyanin said that some residents were being evacuated.
The BBC's Russia editor Steve Rosenberg, who is based in Moscow, heard an explosion in the distance at 06:24 local time (03:24 GMT) in north-west Moscow, with the windows of his home shaking from the blast.
Another explosion was heard at 06:58, he says.
Judging by the conversations on social media, a lot of people in the Moscow area heard the explosions too, he adds.
According to local media reports, as many as 10 drones were shot down over the city, mainly in the Istra, Krasnogorsk and Odintsovo districts.
It follows an overnight drone attack on the Ukrainian capital Kyiv, in which at least one person was reported killed.
Ukrainian officials said falling debris set buildings on fire as Ukraine's air defences intercepted more than 20 drones.
Source: BBC
BDST: 1217 HRS, MAY 30, 2023
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