Overreaction - for the moment, as we're talking about less than thousand people.
But for future larger scale, legit concern.
Meanwhile Russia is planning strict legislation against illegal immigrants. Any staying after visa expires or entering illegally would not be allowed buy, register or drive car or create a bank account, among other things.
I think that's mostly about immigrant workers from the Central Asian former Soviet states, rather than the kind of asylum seekers heading to Europe.