Ukrainian authorities say Russian missile attacks in the south and northeast killed four people during the weekend while Russia says it foiled a Ukrainian drone attack on Moscow.
Ukrainian troops are pushing their counteroffensive to repel Russian forces in the east and south.
But officials in Ukraine's southern region of Zaporizhzhia said on social media that a Russian missile strike left two people dead on Saturday.
Ukrainian President Volodymyr Zelenskyy also said on social media that a Russian missile attack on an educational institution in the northeastern region of Sumy took the lives of two individuals and wounded about 20 others on Saturday.
In a related development, the Russian defense ministry announced on Sunday that Ukraine targeted Moscow with three drones. It said two of them were suppressed by electronic warfare, lost control, and crashed into a business complex in the capital, with the other shot down in the area surrounding Moscow.
Reuters news agency distributed a video it says shows a drone ramming into a high-rise building in Moscow.
This is the fourth time in July alone that a drone strike has been attempted on the Moscow region. The last such attempt came on July 24, when two unmanned aircraft flew into the area with one of them hitting a high-rise office building.