The crime rates are linked to poverty and there's a larger percentage of African Americans living in poverty so that's why the figures are higher.
Moldova is one of the poorest countries on earth. The average income of a Moldovan citizen is around one-tenth of that of the American Blacks. Still, the crime rate in Moldova is extremely low, when compared to the American cities such as Detoilet, Chicago and Miami. So poverty alone is not the reason for a surge in crime.