KYIV, Ukraine — At least 21 people were killed and 30 injured in a Russian missile strike early Friday in southern Ukraine’s Odesa region, authorities said, a day after Russian troops abandoned their positions on an island off the coast of Odesa that has become a symbol of the Ukrainians' stiff resistance.

Sergei Bratchuk, a spokesman for Odesa's military administration, said the missiles were launched by aircraft in the Black Sea and struck a nine-story apartment building. At least two of the dead were children and three other kids were rescued from the rubble. Video of the attack before daybreak showed the charred ruins of buildings in the small town of Serhiivka.

Ukrainian authorities interpreted the attack as payback for Russian troops being forced off Snake Island, a tiny rocky outcrop south of Odesa and just 30 miles from European Union nation Romania's closest coastal city. Moscow, however, called its Thursday withdrawal a "gesture of goodwill" over allegations it is blocking grain exports from Ukrainian ports.

Ukrainian civilians are being killed and injured every day by Russian missile strikes and artillery shelling. On Monday, at least 18 people were killed and dozens injured in a missile strike on a shopping mall in Kremenchuk, in central Ukraine. About 1,000 people were in the mall at the time and at least 20 are still missing.

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MAPPING AND TRACKING: Russia's invasion of Ukraine

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