Moscow has claimed that it is not targetting Ukrainian cities and accused Kyiv of staging footage of civilian attacks to gain support from the West.
Defence ministry spokesperson Igor Konashenkov said that the Donetsk and Luhansk militias have taken populated areas in Ukrainian controlled territories with Russian support.
Konashenkov said that the campaign was a "counter-offensive" and that civilian casualties had been counted among the populations of the two separatist regions, which declared independence in 2014.
He said that Ukrainian forces had not resisted Russian and separatist forces and that they had laid down their weapons and had not been attacked.
Russia launched an invasion of Ukraine on Thursday as President Vladimir Putin warned other nations that any attempt to intervene would be met by "consequences you have never seen".
In the following hours, explosions were heard in Kyiv, Kharkiv and Odesa and condemnation came from around the world. NATO General-Secretary Jens Stoltenberg said the invasion was "cold-blooded and long-planned".
Ukrainians have started to flee some cities and the Russian military claimed to have incapacitated all of Ukraine's air defences and air bases within hours.
President Volodymyr Zelenskyy, declaring martial law, vowed that the Ukrainian army would fight back and defend Ukraine from invasion.
Zelenskyy has also warned about misinformation being spread by Russia and Ukraine's Foreign Ministry warned both Ukrainians and global audiences to only trust legitimate news sources.
But in his statement, Konashenkov accused Ukraine of manufacturing videos of civilian causalities in order to drum up support in the West.
"Staged video recordings have been made in Ukrainian towns, with alleged 'mass casualties' among the civilian population of Ukraine [...] to intimidate the civilian population and broadcast on Western TV channels," he said.
"I should like to emphasise in particular: the Russian armed forces are not carrying out strikes against Ukrainian towns and cities. There is no threat to the civilian population."