There needs to be proof provided, i know the west has low standards for proof and word of mouth as well as rumors and hysteria is good enough for western standards and consumption.
As for Crimea, everyone knew those were Russian forces including me. The Tigr trucks that were seen in Crimea are operated by Russia and not Ukraine, the uniforms were Russians, ect, ect. Looking at east Ukraine, i seen zero Russian vehicles, no Russian military uniforms....nothing.
All of the supposed "proof of Russians" is at best amateur and is spread and overhyped by people that don't know the difference or origin between an AK-47 compared to an M-4, an APC compared to a tank. The media taunts some lame excuses such as "the fighters are professional" reality is that all Ukrainian men have military training, so it should be no surprise that they appear well trained. Other then that people accuse the militias of being Russia because they have AK-47s, how much weaker can their arguments get?