Waterville Mayor Nick Isgro.

Waterville mayor Nick Isgro abruptly stormed out of a Tuesday night City Council meeting after a tense exchange with a resident over his Columbus Day proclamation.

The Waterville Morning Sentinel reports that the exchange between Isgro, a Republican, and Bob Vear, who is in his 60s, came after the council’s unanimous vote to align how the city recognizes holidays with the state.

That means the city will recognize the second Monday in October as Indigenous Peoples Day instead of Columbus Day.

[Waterville councilors could decide to recognize Indigenous Peoples Day after mayor’s Columbus Day proclamation]

During a public comment period, Vear told Isgro that he was drawing negative attention to Waterville and was “not respectful of the people of Waterville,” according to the Sentinel.

That led to a tense exchange when Vear did not give up the microphone after his allotted three minutes and Isgro told him he was “out of line” before shouting, “This meeting is adjourned,” the Sentinel reports.

The meeting continued in Isgro’s absence, and another resident yielded his time so that Vear could continue to speak, the Sentinel reports. Vear called for Isgro to resign and allow the council chair, Republican Sydney Mayhew, to take his place.

“As residents of the city of Waterville, Mayor Isgro, you have tarnished this city again,” the Sentinel quoted Vear as saying.

Earlier this month, Isgro found himself embroiled in a bitter controversy when he issued a proclamation declaring Oct. 14 as Columbus Day.

The proclamation, quoting President Benjamin Harrison, lauded Christopher Columbus as a “pioneer of progress and enlightenment,” whose arrival in the Americas in 1492 prompted the migration of millions of Europeans, who “brought their art, music, science, medicine, philosophy and religious principles to America.”

“The accomplishments of Columbus through his courage and willingness to take unknown risks in exchange for discovery, knowledge, and greatness has trickled down through each generation of Americans, from the early pioneer settlers to the exploration of the vast universe beyond our atmosphere,” the proclamation read.

[Waterville mayor calls Columbus Day a ‘pro-immigrant’ holiday amid backlash over proclamation]

At the Oct. 1 council meeting where Isgro read his proclamation, Isgro drew a mixture of criticism and support from the audience. Exchanges became heated at times, and Isgro at one point threatened to have the police chief eject people from the meeting if they spoke without being recognized.

Opponents called it a “malevolent erasure of a long and violent history of genocide and abuse of indigenous people,” while supporters likened the move to no longer recognize Columbus Day to the Islamic State group’s destruction of cultural artifacts in Syria.

Maine joined a growing number of states — including New Mexico and Vermont — in April when Gov. Janet Mills, a Democrat, signed into law a bill that dropped the state’s recognition of the federal holiday in favor of Indigenous Peoples Day.

That followed a movement among Maine communities, starting in Belfast in 2015, to recognize Indigenous Peoples Day as activists worked to shift perception of Columbus, whose arrival in the Americas ushered in centuries of subjugation, enslavement and genocide against the continent’s original inhabitants.

Bangor, Brunswick, Gouldsboro, Orono and Portland were among the other towns and cities that recognized Indigenous Peoples Day prior to April.

The Sentinel reports that Mayhew on Tuesday night proposed an amendment to the resolution to allow the city to recognize both Columbus Day and Indigenous Peoples Day, but that amendment failed.