Racism in St. Petersburg ?

I'm of Caribbean descent and am interested in teaching English in St. Petersburg, I've previously taught in South Korea.  However, while doing research about Russia in general, I've read quite a few stories about African students being violently attacked in broad daylight.  I don't know if these attacks are isolated incidents or a common occurrence, totally appalling either way.
   
  So, please tell me if you are a person of colour, what has your experience been like in St. Petersberg?  Have you experience racism? Are you concerned for your safety in St. Petersburg or in Russia in general? 

I heard a lot of stories about racism in Korea, but it was after asking questions to people who actually lived there that I was able to make decision to move there.

   Thank you in advance for your responses, they are truly appreciated.


Kind Regards to All!