Protestors in City Hall Plaza called for the firing of a Boston cop and a change in attitude from Mayor Walsh Monday, in response to a video of what they called police brutality in Roslindale.

The footage, posted online Aug. 23, shows BPD Officer Ted Rivera with his hands around the neck of 18-year-old Elvin Vargas during an arrest earlier this month. The video shows police take Vargas into custody after he shouted obscenities at officers — “F— the police,” Vargas yelled — and shows Rivera put his hands around Vargas’ neck as he forces him into a police cruiser.

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Vargas, protestors said, faced brutality for speaking his mind.

“I have a right to say what I want to say,” said Zahra Sirad of Roxbury into a megaphone to a few dozen people on the plaza steps. “And I say ‘f— the police’ all day!”

Sirad was among co-organizers for the event, hosted by Mass. Action Against Police Brutality.

Protestors called for Officer Rivera’s firing, and said they wanted to call attention to a culture of fear and distrust between police and the community.

Boston police, said protest co-organizer Nino Brown in a speech to the few dozen people gathered on the plaza steps Monday, are “choking the life out of our youth” and are “the blue line between the poor and the rich. They are the enforcers of the racist status quo. We are here to raise awareness, to mobilize and continue to organize."

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Protestors also condemned statements from Boston Mayor Marty Walsh about the incident. “I don’t view that as choking,” Walsh reportedly told the Boston Herald.

Sirad called on the mayor to change his tone.

“Did the cop have his hands around a young man’s neck?” Sirad said into a megaphone. “Is that at all acceptable?”

Rahsaan D. Hall, director of the racial justice program for the ACLU of Massachusetts, said the rally should be a reminder to Bostonians their speech is protected, even if that speech is disagreeable.

“They have a right to record the police. They have a right to speak their mind,” Hall told Metro at the protest. “The arrest of Elvin Vargas is a situation where, despite what you might think about what he was saying, he had a right to say those things.”

Police had launched an investigation into the incident, and Vargas’ family was reportedly considering a lawsuit, according to the Boston Herald. Vargas’ lawyer did not return a call from Metro for comment.