"There appears to be an ongoing process by many Warehouse District Business owners to actually discriminate against individuals of color," Forbes wrote, in the hand-delivered letter to Mayor Frank Jackson's office.
"Unfortunately, the situation has escalated to the point that we, NAACP, expect this problem to be resolved at the highest level."
Read Forbes letter to Mayor Jackson (pdf)
In particular, Forbes noted that two West 6th Street bars, Barley House and the Velvet Dog, "have a reputation of harassing and discriminating" against black patrons.
Calls to the night clubs were not immediately returned.
The letter comes a day after Forbes said it was racist for the city to use an organized police response to disperse crowds on West 6th Street after bars close at 2:30 a.m.
Mayoral spokeswoman Andrea Taylor said Jackson plans to meet with the NAACP but provided no further comment.
Other city and business leaders, however, said allegations of racism are nonsense. They added that any security measures added in the last few months are attempts to insure the Warehouse District doesn't implode like the Flats did.
"With thousands of people on the street, the concern is that you mix alcohol and crowds and young adults, that's a bad combination. So what we really want to do is disperse the crowd, get people to go home," said Joseph Marinucci, president of the Downtown Cleveland Alliance.
Residents who live nearby say partygoers have gotten out of control.
"In the last two or three months, it's been getting pretty nasty out," said Jerry Kleinhenz. "We're a little hesitant about the area all of a sudden."
Added Phil Studmire: "I generally try to go in before 2:30 a.m. just because I'm a little afraid...People know where I live so I do keep that in mind when I enter the building."
Ground zero in the fight is the nightclub, Lust, which caters to a predominately black clientele. Police shut it down on Saturday for violating a court order requiring it to close at 1 a.m.
The owner of the building, Bob Raines, of Landmark Management, spoke out today, disputing allegations of racism made by both the NAACP and the owner of Lust.
He said Lust is getting tossed for one reason -- it changed from a restaurant to a dance club -- violating its lease and becoming way too loud.
"When the law is against you, and the facts are against you, you make up arguments that simply aren't true," Raines said.
Downtown City Councilman Joe Cimperman added that there's an effort to keep the Warehouse District safe so "the police are going to respond to where the problems are."
Some residents, however, feel the city is overreacting.
"The noise from the bars is a little annoying," said resident Meredith Wagner, "but that's what we get for living down here."