Russian forces struck a market in the city of Sloviansk in eastern Ukraine on Tuesday, killing a woman and wounding at least three other people, police said.
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 clear what munitions had been used in the attack on the frontline city in the Donetsk region, or how many people had been at the market when it was hit.
Police said the market had been closing for the day, but that some shops had still been open.
"Together with police we are documenting the shelling of the city,"
Prosecutor Oleksandr Bakumenko
"Together with police we are documenting the shelling of the city," Ukrainian Prosecutor Oleksandr Bakumenko, who was at the market after the attack and wore a vest that read "war crimes investigator," told Reuters.
Sloviansk Mayor Vadym Lyakh said on Facebook that the city had come under mass shelling and urged residents to stay in shelters.
Russia has denied targeting civilians since invading Ukraine on Feb. 24. Ukraine says Russia has been using inaccurate Soviet-era missiles to hit military and critical infrastructure, killing many civilians in wayward strikes.
Tuesday was the eighth anniversary of Ukraine recapturing Sloviansk from Russian proxy forces of the self-proclaimed Donetsk People's Republic.
Russia has secured almost complete control of the neighboring Luhansk region and is turning its attention to Sloviansk as a gateway to capture the rest of the Donetsk region. It has fired several missile salvos into Sloviansk in recent days.
In a residential neighborhood on another side of the city, several houses were damaged and firefighters were tackling flames in a burning house where a missile hit on Tuesday afternoon.
Rescue workers said at least two people had been taken to hospital from that strike.
Military spokesman Oleksandr Motuzyanyk told a briefing that Russian forces were focusing their efforts on the Luhansk and Donetsk regions, firing artillery along the entire front line. He said Ukraine's army was trying to prevent Russia from creating conditions to launch an assault on Sloviansk.