A witness to Saturday’s demonstration at the Bunker Hill Monument that left dye on the pavement says the participants were part of a hate group that left a larger stain on the community.

A group of 15 to 20 people allegedly set off flares or fireworks around 11:30 p.m. by the monument, leaving dye on the ground by the William Prescott statue, according to the National Park Service. The monument and statue were not damaged and there will be no charges in the incident.

But a witness said he called the police on the demonstrators, who he described as marching up to the monument with burning flares and chanting with a bullhorn.

“They were clearly doing it to be threatening, to try and intimidate the neighborhood,” said the witness, who did not want to identify himself for fear of retaliation. “We have to call it what it is, which was a racist group trying to promote their ideology.”

The next day, the group “Patriot Front,” described as a hate group by the Southern Poverty Law Center, posted photos of the demonstration on their Twitter account.

Patriot Front was blamed for plastering anti-immigrant posters throughout East Boston in February. At the time three members were arrested and one was charged with slapping a police officer.

Police will not say if they are investigating the group.

On Monday, Mayor Martin J. Walsh decried the alleged vandalism, calling it racist.

“It was said, it’s not just vandalism but downright racism,” Walsh said. “We won’t tolerate that, we won’t stand for that.”

This is a developing news story; stay with 7NEWS on-air and online for the latest details.

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