All my evidence is anecdotal, and I have no means of confirming it on my own.

When I first looked over this post, there were 3-4 comments, all seemingly pro-russia. I see some points being made that are remarkably similar to official Russian positions on issues. Its really similar to when I see a post about China. A whole bunch of users surface abruptly with lots of comments favorable to China. Both of these countries have large, well documented operations to comment extensively on Western media sources. And I'm sure that many HN users like Russia and like China. But it's hard to shake the feeling that there is some astroturfing going on.