NEW YORK (CBSNewYork) — Demonstrators gathered at City Hall in support of the NYPD Friday evening, but they were met right away with a rival demonstration by critics of police policies.

A pro-police rally organized by a Facebook group called “Thank You NYPD” was held as a counterpoint to the recent protests against police brutality. As CBS2’s Matt Kozar reported, supporters gathered under the hashtag #BlueLivesMatter, and about 75 pro-police demonstrators were at the scene as of 5 p.m. Friday.

The number had grown to about 100 by 6 p.m.

PHOTOS: Dueling Pro- And Anti-Police Rallies

Organizers said they’re showing support for the “Brave women and men who keep the streets of New York safe and risk their lives doing so.”

But neither police Commissioner Bill Bratton nor police unions endorsed the rally, reportedly out of concerns about violence.

The pro-police demonstrators said police officers are being unfairly maligned. They said police officers saved lives amidst the attacks of Sept. 11, 2001, and also rushed in to save people during Superstorm Sandy in 2012.

“Obviously, there is something wrong. That’s why we’re all here. We’re all trying to figure out what the anti-cop side of this whole thing seems to be really brazen and brash; I mean, now, people are attacking cops for no blatant reason,” a man said as he expressed support for the police.

Police supporter Philip McManus of Queens said he wanted to balance out the dialogue.

“I do believe that the silent majority needs to get off the couch and they need to get involved, and they need to stand up for law and order,” he said.

Meanwhile, about 100 demonstrators gathered for a counter-protest called “No Thank You, NYPD” to demonstrate against the pro-police rally.

“What happened with the grand juries for Mike Brown; for Eric Garner, the cops got off scot free,” said one woman who was protesting against police policies. “And as long as they can get off scot free and do what they do without impunity, this war is going to continue to happen, and people are saying, ‘Enough is enough.’”

As WCBS 880’s Jim Smith reported, the pro-police supporters chanted, “blue lives matter.”

“I believe that I have a right to speak just like anybody else,” one supporter said.

Police kept the two groups separated by metal barriers. Across a 10-foot wide no man’s land between the barriers, protesters fired back, “black lives matter.”

“Why are we saying that? Because it appears, in this city, that it doesn’t matter,” a protester said.

There were also a number of verbal confrontations between protesters and police supporters, but no physical confrontations, Kozar reported.

Around 6 p.m., the anti-police protesters moved out of City Hall Park for the first of several marches, and marched up Broadway, across Chambers Street, and along Nassau Street around City Hall.

The anti-police protesters later began marching took over part of the Brooklyn Bridge. Traffic was initially still moving on the bridge, but at a slowed pace.

But police shut down the Manhattan-bound side of the bridge for a period of time around 7:45 p.m.

Some sign-throwing and some pushing and shoving had been observed on the Bridge at the Park Row entrance, but there had been no arrests as of mid-Thursday evening. Police appeared to be trying to push the protesters off the bridge and back onto Park Row, CBS2’s Joe Biermann reported.

The anti-police protesters later returned to City Hall Park, where some protesters were heard chanting, “Commies go home.”

Protesters against police policies later resumed marching, heading down Fulton Street against traffic and passing through Chinatown. They chanted, “If we don’t get no justice, then you don’t get no peace.”

There were no arrests reported during the protests Friday evening.

Earlier Friday, Mayor Bill de Blasio held a meeting with some of the organizers of the recent protests against a Staten Island grand jury’s decision not to indict an officer in the death of Eric Garner.

The mayor called the 40-minute meeting with members of Justice League NYC productive with both sides committed to healing, 1010 WINS Derricke Dennis reported.

The group presented a list of demands, including the elimination of the “broken windows” policing strategy in which officers target enforcement of smaller crimes to prevent more serious ones.

The mayor said he believes in the “broken windows” theory of policing and said he does not believe it unfairly targets minorities.

“I think we have a broader obligation as we continue reforms and the relationship between police and community and in our approach to policing, to make very clear that we will not accept unequal treatment,” de Blasio said.

The group also wants Officer Daniel Pantaleo and “all officers responsible for the death of Eric Garner” fired, according to its website.

In addition, it wants the state to appoint a special prosecutor to investigate criminal cases involving the use of force, including deadly force, by police officers.

“”The meeting was productive. We discussed our demands and we look forward to ongoing conversations,” said Justice League NYC President Carmen Perez.

Perez called for a “culture shift in policing in New York City” and said the group wants to meet with Police Commissioner Bill Bratton.

Following the meeting, de Blasio shook hands with newly-promoted men and women of law enforcement in the NYPD. He said he hoped to make it clear to the Justice League and other activists that violence against police officers is not acceptable, CBS2’s Sonia Rincon reported.

The mayor noted the Justice League was quick to affirm his stand against violence, WCBS 880’s Rich Lamb reported.

“They will work with the police to identify anyone who seeks to harm the police or harm anyone and undermine their non-violent, peaceful, progressive movement,” de Blasio said.

De Blasio told reporters after the meeting that he listened to a list of the protestors demands and didn’t agree with all of them.

“I’ve said very clearly that I believe in the broken windows theory of policing. I do think, and I’ve said this also, that we need to do a better job explaining what it means in the year 2014 and what it will mean in the year 2015,” de Blasio told reporters.

Later at One Police Plaza, the mayor would make that point again, saying broken windows policing brings down crime.

Bratton also spoke in favor of the broken windows policy, 1010 WINS’ Roger Stern reported.

“It works, and it is, in some respects, it’s the penicillin that deals with the many illness that are inflicting the city,” he said.

De Blasio got a polite response as he praised newly-promoted detectives and sergeants for continuing to keep crime low and keep the peace during all the protests.

“You’ve done that and that is not easy. But you’ve done it day in and day out,” the mayor told the detectives and sergeants. “The eyes of the nation – in fact, the eyes of the world – have been on this city and this department, and the result is the respect for the NYPD has grown. And you have upheld the best traditions of our democracy.”

A $25,000 reward is currently being offered for information leading to the arrest of six suspects in connection with a clash between protesters and police on the Brooklyn Bridge on Saturday.

One suspect, 43-year-old Robert Murray, was arrested and charged Thursday in connection with the incident.

A third suspect was also in custody Friday evening.

Garner, a 43-year-old father of six, died after he had been stopped by police for allegedly selling loose, untaxed cigarettes.

Pantaleo and other NYPD officers stopped Garner on the street in Tompkinsville. A video shot by an onlooker showed Garner telling the officers to leave him alone and refusing to be handcuffed.

Pantaleo responded by wrapping his arm around Garner’s neck in an apparent chokehold, which is banned under NYPD policy. The heavyset Garner, who had asthma, is heard gasping, “I can’t breathe.” He later was pronounced dead at a hospital.

The New York City Medical Examiner’s office ruled Garner’s death a homicide, caused by the officer’s apparent chokehold as well as chest and neck compressions and prone positioning “during physical restraint by police.”

Pataleo’s lawyer and police union officials have argued that the officer used an authorized takedown move, not a chokehold, against a man who was resisting arrest. They also said Garner’s poor health was the main cause of his death.

While the grand jury decided not to indict Pantaleo in the case, he is still subject to an ongoing probe by NYPD Internal Affairs and a federal investigation.

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