STORY: The attack caused a huge fire and sent dark smoke billowing into the sky, footage captured by an eyewitness and circulated by President Volodymyr Zelenskiy showed.
A Reuters reporter saw the charred husk of a shopping complex with a caved-in roof. Firefighters and soldiers were pulling out mangled pieces of metal as they searched for survivors.
Zelenskiy said more than 1,000 people were in the shopping center at the time of the attack. He gave no details of casualties but said: "It is impossible to even imagine the number of victims."
"It's useless to hope for decency and humanity from Russia," Zelenskiy wrote on the Telegram messaging app.
A rescue operation was under way and nine of the wounded were in a serious condition, said Kyrylo Tymoshenko, deputy head of the presidential office.
There was no immediate comment from Russia, which denies deliberately targeting civilians.