KYIV (REUTERS) - Shelling hit residential houses and a shopping district in Kyiv's Podil district late on Sunday (March 20), killing at least eight people, according to Ukraine's Prosecutor-General.

"According to the information we have at the moment, several homes and one of the shopping centres (were hit)," city mayor Vitali Klitschko said on his Telegram channel.

He said rescue teams were putting out a large fire at the shopping centre, while other details were still to be confirmed.

The Kyiv department of the state emergency service said four people had been killed.

A new, longer curfew was being introduced in the Ukrainian capital because the authorities expected further shelling by Russian forces.

Mr Klitschko had earlier on Monday announced a“reinforced curfew” in the Ukrainian capital from 8pm (1800 GMT) until 7 am on Wednesday.

Parts of the city have come under fire repeatedly from Russian forces.

“The reason for the curfew is linked to the likelihood of new shelling,” he said later on Monday on national television.

Reuters was not immediately able to verify the reports on the ground.

Elsewhere in the country, authorities in Odessa accused Russian forces of carrying out a strike on residential buildings in the outskirts of the Ukrainian city early on Monday, the first such attack on the Black Sea port city.

The city council said there were no casualties although the strike caused a fire. “These are residential buildings where peaceful people live,” Mayor Gennadiy Trukhanov was quoted as saying. Russia denies targeting civilians.

Russia's invasion of Ukraine has killed thousands of people, displaced more than three million and raised fears of a wider confrontation between Russia and the United States.

Russian President Vladimir Putin says the "special military operation", which started on Feb 24, is aimed at disarming Ukraine and rooting out dangerous nationalists.