Some activists and elected officials are criticizing the NYPD's handling of protests over the death of a Baltimore man critically injured in police custody.
The group claimed Thursday that the NYPD was overly aggressive and at times violent.
Police Commissioner William Bratton said 143 people were arrested Wednesday night during a rally and march over the death of Freddie Gray. Gray suffered a severe spinal injury in the custody of Baltimore police. He later died.
Bratton said police would be "more assertive" in dealing with demonstrators who try to block roads or bridges than they were during December protests in the wake of the Eric Garner grand jury decision.
"It's the balancing we do," he said. "You have the right to protest. We'll work with you to allow you to protest. Protest as much as you want."
At the start of the rally in Union Square Wednesday evening, police made announcements and handed out fliers asking protesters to stay off the roads and to not block traffic. When those orders were ignored, police had to take action, officials said.
"One thing is clear: when police give you instruction, you follow instruction. It's not debatable," said Mayor Bill de Blasio.
De Blasio insisted that there was not a fundamental change in police treatment of demonstrators.
"The strategic approach is exactly the same," he said. "We are going to respect non-violent protest and we will accommodate it in all sorts of flexible ways."
NYPD Chief Jim O'Neill added, "Everyone in this room watched what unfolded in Baltimore, so of course it was on my mind, but not as far as how we strategized."
Protesters who marched on bridges and highways during the Eric Garner demonstrations last December, sometimes shutting them down, may have expected similar latitude Wednesday. They say they instead encountered stricter police on the ground.
Jason Walker said he was mistreated and unjustly cuffed during the protests.
"There was no sidewalk for us to move to," he said. "They said, 'Move to the sidewalks.' We said, 'Where?' Then four officers tackled me down to the ground."
Police aren't discouraging protests, Bratton said.
"This is a city that likes to protest. It's something that's ingrained in New Yorkers," he said.
In a statement from activist group Communities United for Police Reform, spokeswoman Priscilla Gonzalez said: “Our communities have been brutalized and killed by police despite following the law for decades, and last night New Yorkers were once again brutalized by the NYPD for simply protesting."
