If you go out after 7 pm most of the year half the people downtown are immigrants selling drugs, doing petty crime or whistling and annoying women.
I see and live that, and have female family members and friends being assaulted by these people, and they are immigrants.
It's not a matter of skin color, but demographics.
They are young, male, unemployed and from a different culture, they are more prone to decaying and aggressive behavior. But it's a fact, they make the cities less safe and they dominate the stats in petty and violent crimes.