At least 18 people, including two children, have lost their lives as a result of Ukrainian shelling on the Russian city of Belgorod on Saturday, CNN reported, citing Russia's Ministry of Emergency Situations.
This attack came after Moscow launched a major aerial assault on Ukraine.
A "massive" attack on downtown Belgorod was the cause of the casualties.
Dmitry Polyanskiy, Russia's first deputy permanent representative to the United Nations, stated on Saturday that his country has asked for an emergency meeting of the UN Security Council in response to the incident, according to CNN.
"This crime will not go unpunished," the defence ministry of Russia said in a statement following the shelling.
"The Kyiv regime... is trying to divert attention from the defeats on the front lines and to provoke us into taking similar actions," it said, according to CNN.
The bombardment on Saturday follows Russia's largest airstrike against Ukraine since the beginning of its full-scale invasion, which was carried out overnight on Thursday and into Friday and resulted in at least 40 deaths and over 150 injuries.
For more than a year, Ukrainian forces have been attacking Russian areas close to the border virtually every day. While occasionally civilians have been killed, this would be one of the bloodiest incidents so far.
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