Okay, so skin heads don't beat up African Immigrants? Please open your eyes. Denial is not a pretty thing, it just makes you look silly.
The racism I see from whites vis a vis blacks is more of the snotty, condescending kind and is reflected more in attitudes than actual violence.
In the case that you referenced, it was telling that those morons in Portland attacked a peaceful Ethiopian rather than go to the PJs in NE Portland and dare any black folk who lived there to come out and fight.