Air defences in Ukraine's capital of Kyiv were repelling a Russian air attack early on Tuesday morning, the city's military administration said.

Reuters witnesses reported several explosions in the capital after Ukraine's air force announced a missile threat across the country.

According to preliminary information, missile debris fell on a private building in one of the capital's districts, the city's military administration said on Telegram.

There was no fire or damage, as well as no reports of casualties, it added.

Separately, unidentified infrastructure was hit in a Russian missile attack in the town of Shostka, in the northern Sumy region, authorities said on Telegram. Local Telegram channels reported rounds of explosions in the area.