If city officials don't acknowledge that the police department "has created a system of apartheid in this city of New York, we are going to show you that there will be no peace," said Kirsten John Foy, a top aide to New York Public Advocate Bill de Blasio.
Gathering in Brooklyn's Grand Army Plaza, community leaders and politicians said that a culture of discrimination against minorities exists within the New York Police Department and that NYPD officers are randomly stopping and searching hundreds of thousands of minority residents each year.
A series of investigative reports by The Associated Press have revealed how after the 9/11 attacks the CIA helped the NYPD build domestic intelligence programs that were used to spy on Muslims.
Police Commissioner Raymond Kelly has defended his department's aggressive policing of high-crime neighborhoods - including the stop-and-frisk tactics. He says the practice has made the city safer by plucking out crimes both big and small. The CIA has also said its internal watchdog found nothing wrong with the spy agency's close partnership with the NYPD.
But City Councilwoman Letitia James told Saturday's gathering of more than 100: "Now is the time to act because too many people are being hurt."
She said the rally was being held in a "symbolic space to demand more police accountability."
The Brooklyn plaza is the endpoint of the West Indian Day Parade, which in September brought participants nose-to-nose with police. The annual celebration has been marked by violence in recent years, with two people killed last year in a wild shootout near the parade route.
Jumaane Williams, a black City Council member, was handcuffed while walking on a Brooklyn sidewalk during the parade, after he said he received permission to do so from other officers.
Last month, Kelly said he was disturbed by racially hateful comments posted on Facebook regarding the boisterous parade and which NYPD officials said might have come from police officers.
Participants were called "animals" and "savages."
The NYPD Internal Affairs Bureau has opened an investigation into the postings.
"This is not an anti-NYPD rally," Williams said at the start of the rally, where a round of applause greeted officers there.
He said ethnic communities would welcome a police presence that worked closely with them to weed out crime.
However, the Democratic councilman added, Mayor Michael Bloomberg and his police commissioner "have refused to acknowledge that a problem even exits."
The rally also included Manhattan Borough President Scott Stringer and members of the Center for Constitutional Rights, the Muslim American Civil Liberties Coalition and the New York Civil Liberties Union.
The AP investigation "detailed how, over the past decade since 9/11, the NYPD has been monitoring and profiling virtually every layer of NYC Muslim public life, often with no suspicion of wrongdoing," said Linda Sarsour, a member of the Muslim coalition.
Foy, de Blasio's director of community relations, also was taken into police custody while walking along the parade route in September.
On Saturday, his message to the mayor and police commissioner was: "We're not going to let you smile at us while clubbing us over the head."
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