Russia is denying that they are up to anything.
Russia says it has no military personnel in eastern Ukraine. At the same time Russian mass media is full of stories about American “mercenaries” operating in Ukraine.
Russian claims of NATO mercenaries or even special forces destabilizing Ukraine will be bolstered by captured American equipment that will be put on display. They've done it before.
UPDATE: Russia called for a UN Security Council meeting today:
The U.N. Security Council has called an emergency meeting at Russia's request to discuss the growing crisis in Ukraine.
No word on what is going on, so far.
One can assume that the Russian representative won't tearfully apologize for Russia's responsiblity for the growing crisis.
My worry is that Putin is checking a diplomatic box to pretend he consulted with the world before sending his troops in to the eastern corner of Ukraine.
I honestly didn't think Putin would risk a war with Ukraine that could go badly and tarnish the reputation built on Crimea. But events point to Russia beginning a war.