A drone attack in Moscow has caused minor damage to several buildings, officials say, according to the BBC.

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 shot down several drones as they approached the Russian capital, officials said.

It is not immediately clear where the drones had come from.

Unconfirmed reports say that about 20 drones were involved, while Russian authorities said several of them fell on buildings after being downed.

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.

Sobyanin said that some residents were being evacuated. On Telegram, he also reported that two people had sought medical assistance, but that no one was taken to hospital.

The strikes on Moscow follow 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.