No, you didn't read it at all...because if you had, you'd have seen the PROOF that it wasn't part of any BLM or MMM march. It was proven by observations made of the time of day - the streetlights were on, so it happened after the other marches:
The video of that particularly venal bromide was taken from a window high above Murray Hill, an upscale neighborhood in the middle part of Manhattan’s east side. It has been replayed and repeated over and over as part of the coverage of the tragic killing of officers Ramos and Liu, including on MSNBC.
And yet, evidence shows the group that engaged in the death chant against police weren’t part of Millions March NYC. And if they did indeed march on Dec. 13, they did so long after the larger protest had moved downtown. They were not part of the main group.
For one thing, according to the video, which was posted to Youtube the same day as the protest, the “dead cops” chant took place after sunset. You can see from the video that city lights are already on. The group starts by chanting “hands up, shoot back,” before switching to the death chant, and then an unintelligible chant at the end of the approximately 2 minute clip.
That's the proof. PROOF.
But I get it - you just can't stop yourself from blaming BLM.
Oh, and one more thing - you're claiming it couldn't have been spontaneous? I guess that means that the riots that took place nationwide after the first Rodney King verdict were all secretly coordinated by BLM (which of course didn't exist yet) in a secret location deep inside Harlem....