Russian military forces launched a large-scale attack on Ukraine's capital Kyiv on Friday, an assault that residents described as "the end of the world." At the same time, they are tightening their grip on the eastern front.

A strike that killed six was the latest in a series of aerial assaults, many of which have targeted the power grid in an effort to deprive Ukrainians of energy as winter looms.

Russia unleashed a major missile and drone attack on Kyiv early Friday, killing four people, starting fires and scattering debris across many districts of the capital, Ukrainian authorities said.