Police investigating whether alt-right group is linked to fireworks incident near Bunker Hill Monument

The Bunker Hill Monument in Charlestown, as pictured in May 2016.Craig F. Walker/Globe Staff/File/Globe Staff

Demonstrators who set off flares near the Bunker Hill Monument in Charlestown late Saturday had their faces covered, and law enforcement officials are trying to determine whether they are linked to an alt-right group, authorities say.

Boston police were called to the monument area around 11:45 p.m. and were met by a park ranger, who told them he’d been informed by witnesses that up to 20 people with “cloths covering their faces” had lit off flares and paint canisters placed at the base of the William Prescott statue, a department incident report said.

Demonstrators fled the scene in cars, and burn residue and specks of blue paint were left on the statute and its base, the report said. Boston police and the National Park Service continue to investigate the incident. No arrests have been made, Boston police said Tuesday evening.

The Patriot Front, an organization that critics have labeled a white supremacist group, said on Twitter that “activists demonstrated at the Bunker Hill Monument in Charlestown, Massachusetts in commemoration of national independence, and in a declaration of resistance against tyranny.”

Boston police Sergeant Detective John Boyle, a department spokesman, said authorities are investigating whether the Patriot Front was involved in the incident.

The park service had released a brief statement on the matter Monday, saying that “15-20 individuals ignited some sort of fireworks or flares around 11:30 pm Saturday night in the vicinity of the [William] Prescott Statue next to the Bunker Monument. The park curator assessed the area this morning and reports no damage to the statue or adjacent area. The investigation remains open. We have nothing additional to report.”

A park service spokesman declined further comment Tuesday, citing the ongoing probe.

The Anti-Defamation League and the Southern Poverty Law Center, two leading hate group watchdogs, have described the Patriot Front as racist and anti-Semitic.

“Patriot Front is a white supremacist group whose members maintain that their ancestors conquered America and bequeathed it to them alone,” the ADL says on its website. “They define themselves as American fascists or American nationalists who are focused on preserving America’s identity as a European-American identity.”

The law center has a similar assessment on its site.

“Patriot Front (PF) is a white nationalist hate group that formed in the aftermath of the deadly ‘Unite the Right’ rally in Charlottesville, Virginia, of August 12, 2017,” the law center says. “The organization broke off from Vanguard America (VA), a neo-Nazi group that participated in the chaotic demonstration.”