I'm sure there are some of those, but they're not the official "Black Lives Matter" movement. (So far as such a thing can be said to exist in a real sense. It seems to be more structured than the Tea Party, Occupy Wall Street, or the Alt Right movement.) The official Black Lives Matter movement is self-destructive, socialist, and explicitly anti-family.
They quixotically riot and protest legitimate police violence but ignore many of the real abuses that are occurring.
I also think that it is clear that they are misidentifying symptoms as causes and offer no real solutions while causing destruction that will lead to short-sighted appeasements which will hurt them even further.
There is no extermination order,