Remember the Jill Stein recall that immediately stopped after finding a lot of fraud in Detroit.
This type of crap happens in every Democrat controlled major city from Miami to Philadelphia to Chicago and so on and so on. Happens in smaller areas they control as well, but much easier in areas with millions of registered voters where they know who does and doesn't vote and they can use those that don't have a history of voting along with all the invalid people on the voting rolls to rig the elections in their favor. You'll notice these areas are almost always last to get their official numbers reported because they need to know how many fraudulent to come up with for the steal.
Remember the Jill Stein recall that immediately stopped after finding a lot of fraud in Detroit.