MOSCOW/KIEV -- Ukrainian troops intentionally fired artillery shells at the town of Donetsk in Russia's Rostov region, Russian Investigative Committee said on Monday.
"Unidentified Ukrainian armed force personnel, National Guards and the Ukrainian ultra-nationalist group Right Sector shelled the town of Donetsk from the Ukrainian territory," Interfax news agency quoted the committee spokesman Vladimir Markin as saying.
A local resident was killed in Sunday's cross-border shelling and another was wounded, Markin said.
Latest reports showed that Ukrainian troops fired at least seven shells and six exploded, according to the spokesman.
The committee also said that it would use relevant satellite data in order to confirm who was responsible for the shelling of the Russian town, which lies near the border with Ukraine's Lugansk region.
"We'll use satellite data to find out which unit of the Ukrainian army, National Guards or the Right Sector was in the zone where these shells came from," Markin said.
"It will allow us to verify the commander that ordered the shelling of the Russian territory," and they would no doubt be punished, Interfax news agency quoted Markin as saying.
Rostov Governor Vasily Golubev said on Monday he would call on forces to enhance border protection in the region.
Ukraine said Sunday it had nothing to do with the shelling, urging Moscow to be "objective and unbiased" when assessing the causes of the incident.
Moscow has repeatedly warned of a humanitarian catastrophe in eastern Ukraine, claiming more than 20,000 Ukrainians had applied for refugee status in Russia.
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