'Massive' Russian shelling on Sloviansk, casualties reported

Russian forces are pounding Sloviansk with "massive" shelling, its mayor said on Tuesday, as the eastern Ukrainian city becomes Moscow's next target in its campaign in the Donbas region.

"Sloviansk! Massive shelling of the city. The centre, the north. Everyone, take shelter," Vadim Lyakh wrote on Facebook.

Russian forces struck a market in the city of Sloviansk in eastern Ukraine, killing a woman and wounding at least three other people, police said separately.

A Reuters reporter on the scene saw yellow smoke billowing up from an auto supplies shop, and flames engulfed rows of market stalls as firefighters tried to extinguish the blaze.

It was not immediately what munitions had been used in the attack on the city, which lies in the Donetsk region.

Police said it was not clear how many people were at the market at the time of the attack but that the market had been in the process of closing for the day, with some shops still open.

Ukrainian authorities have on several occasions urged Sloviansk residents to leave the region as the frontline approaches the city following Russia's capture of Severodonetsk and Lysychansk in the neighbouring region of Lugansk.

Russian bombardment has killed at least six people and injured another 19 since Sunday in the city with a pre-war population of around 100,000.

Sloviansk and regional administrative centre Kramatorsk remain under Ukrainian control and are Russia's next goals in its campaign to conquer the eastern Donbas region.

In 2014, pro-Moscow separatists briefly took control of Sloviansk in their conflict with the authorities in Kyiv.