Demonstrators are planning to protest the annual Christmas Tree Lighting Ceremony at Rockefeller Center tonight in response to the grand jury's decision not to indict the cop accused of placing Eric Garner into a fatal chokehold. Mayor de Blasio has already cancelled his appearance at the lighting ceremony as protesters have begun announcing their intentions via the #ShutItDown hashtag on Twitter.

Some are planning to organize at Union Square around 6 p.m., then march up to Rockefeller Center for the 7 p.m. Christmas tree lighting. There are also planned protests at Times Square tonight.

The NYPD sent out a media advisory before the Garner announcement saying heavy traffic is expected for the vicinity of Rockefeller Center and Radio City Music Hall between 3 p.m. and 11 p.m. They added that the following streets will be subject to closures from about 3 p.m. until the conclusion of the event: 48th, 49th, 50th, and 51st Streets between Avenue of the Americas and Fifth Avenue.

In the past few days, Police Commissioner Bratton and other politicians have spoken out about cops preparing to deal with "professional agitators" who may "act up" after the decision was made.

Cops have already started checking people's IDs and shutting down streets around the area.