Ukrainian forces defiantly pushed back against threats by Russia to annex territory it controls Saturday, while Moscow replaced a top general in charge of logistics after a series of snafus that contributed to recent battlefield losses by Russian troops.

The fighting raged as Russian proxies in four Ukrainian provinces conducted the second day of voting in what Western officials have called "sham” referendums to become part of Russia. Some residents reported seeing soldiers in ski masks accompanying election workers and going house to house to coerce people to vote.

The referendums — which are expected to culminate in the annexation of an area larger than Portugal — have raised alarm in Western nations because Russia, the nation with the world’s largest nuclear arsenal, has signaled that after annexation, it would consider Ukrainian attacks in the territory violations of its sovereignty and defend it by any means necessary.