Hours after Mayor de Blasio called on civil rights activists to "put aside protests," a small group of demonstrators gathered yesterday in Grand Central Terminal to peacefully exercise their First Amendment rights. Holding signs such as "More Justice = More Peace," the protesters simulated the chokehold death of Eric Garner and staged a silent die-in on the floor of the terminal. One man's sign read, "The mayor has asked us not to protest; that makes it even more important that we continue to do so."

De Blasio had requested that protesters hold off on demonstrations until after the funerals for the two officers who were assassinated in broad daylight on Saturday. But the group Ferguson Action quickly issued a letter, cosigned by other grassroots organizations, insisting they would not be silenced and criticizing the NYPD unions for their "reckless attempts to conflate constitutionally protected protest activities with the tragic murders of officers Ramos and Liu." Here's the letter, in full:

"We renew our condolences to the families and friends of those injured and killed this weekend. As those who stand with the victims of police violence, we know all too well the deep sense of loss that a community feels when they lose a loved one. They are in our thoughts and prayers as we continue our movement for justice.

"This is not a time for political grandstanding and punditry. Unfortunately, we continue to see elected officials and police leadership twist this tragedy into an opportunity for them to silence the cries for justice from families who have lost their loved ones to police violence. Our families matter, too.

"Those exercising their First Amendment rights to secure a justice system that works for ALL are being thrown under the bus by police departments and their union leaders who want to skirt their responsibility to our communities.

"This weekend, Patrick Lynch used his role as the President of the largest police union in New York to essentially declare war on Black communities. This is unacceptable and should be condemned. Under his leadership, the police union has resisted nearly every positive criminal justice reform— including the end of discriminatory stop and frisk practices, protecting the Miranda rights of those arrested, and inviting community input in the creation of policies that govern the police.

"Commissioner Bratton must also immediately end his shameful attempts to use the deaths of these officers to attack democracy by advancing unfounded claims to connect this tragedy to protests. A troubled young man who began his day by attempting to kill his ex-partner, shot two officers and then killed himself has nothing to do with a broad non-violent movement for change. The NYPD is conveniently ignoring the facts surrounding this tragedy in order to score cheap political points.

"Commissioner Bratton and Patrick Lynch must immediately apologize to New Yorkers who desperately want change in the city. Mayor DeBlasio and other elected officials should condemn these opportunistic distractions that attempt to avoid meaningful reform.

"A concerted attempt to defame the millions who have acted on behalf of those lost to police violence proves that the NYPD leadership has no intention of creating any trust between this department and the communities they purport to serve.

"Our communities are in crisis. We've responded by meeting in our homes, offices, and schools— and walking out of them, with our hands up. Thousands of others have organized small actions that when woven together have tremendous impact. The problem isn't the diverse voices that participate in dissent, a cornerstone of our democracy.

"The problem is a discriminatory pattern of police violence that continues unabated and that police brass don't care to stop it.

"This movement was sparked by the grief that millions across the country have felt. Joining Eric Garner, Mike Brown and Tamir Rice are the thousands of lives lost in the last decade to police shootings. We are in the streets because we are fighting for the right to live our lives fully and with dignity, without the threat of unconstitutional police violence and repression.

"Our work continues and we invite those who stand on the side of justice to join us."