Dozens of injuries were reported in Kyiv and other Ukrainian cities.
Russia has continued a nearly 19-month-long invasion of neighboring Ukraine. Recently, though, the Ukrainians have gone on a counteroffensive, fighting to reclaim occupied territory.
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President Joe Biden spoke with French President Emmanuel Macron, German Chancellor Olaf Scholz and U.K. Prime Minister Rishi Sunak about the developments in Russia.
Biden and Vice President Kamala Harris were also briefed by their national security team on the developments in Russia and will continue to receive updates throughout the day, the White House said Saturday.
-ABC News' Justin Gomez
The governor of the Lipetsk region, which is about 300 miles south of Moscow, said a column of Wagner troops has been spotted in the region, Russian state media reports.
A NATO representative said the alliance was watching what was happening in Russia on Saturday.
"We are monitoring the situation," spokesperson Oana Lungescu said.
-ABC News' Rashid Haddou
A governor of the Voronezh region, about 300 miles south of Moscow, says Russia's armed forces are conducting "operational combat operations" there as part of "counter terrorism operation."
Earlier the region's government reported a column of Wagner Group fighters was moving through the region, an area between Rostov-on-Don and Moscow.
"In the bounds of the counterterrorist operation on the territory of the Voronezh region, the armed forces of the Russian Federation are conducting necessary operational combat operations," the official said. "We will inform further about the development of the situation."
-ABC News' Patrick Reevell
