The endorsement of Donald Trump by the Fraternal Order of Police appears to have driven a wedge between many black cops and their white brothers in blue.

And nowhere is the split more visible than in Philadelphia, where the local FOP chapter has fallen in line and also endorsed the Republican presidential candidate — over the objections of a group that represents some 2,500 African-American officers in the city and which has branded Trump an "outrageous bigot."

"Our Local FOP is saying that our people have to follow the national lead," Rochelle Bilal, head of the Philadelphia Guardian Civic League, told NBC News. "We are saying you don't have to vote for Donald Trump and the national FOP should have stayed out of this election."

Bilal, a former Philadelphia cop who retired after 27 years on the force, said "those of us in law enforcement who are people of color are constantly trying to build bridges to the community, we're trying to build trust in law enforcement."

But "the Trump campaign is racist, sexist, anti-gay. It's a divisive campaign that's now dividing law enforcement," she said.

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