Every year in mid-July, a scene straight out of an Italian village unfolds in a tight-knit neighborhood of Newton, Mass. A boisterous procession of residents parades down the middle of Adams Street at night, carrying lit candles and pulling a statue of the Blessed Virgin in a cart.

For 90 years, the street had a centerline painted red, white and green — the colors of the Italian flag — in a nod to the many Italian Americans in the neighborhood, Nonantum, and their annual festival.

Then, one night last month, the city sent a crew to replace the tricolor line with standard reflective yellow stripes. Newton’s mayor said the change was made to improve traffic safety, citing an analysis that found Adams Street had a higher-than-average number of crashes.

To some Nonantum residents, it was an assault on their heritage — especially given the timing, three weeks before the start of their beloved festival.

“These lines are not just paint, they are sacred symbols of Italian American pride, religious tradition and community identity,” the St. Mary of Carmen Society, the local group that holds the festival, wrote in a statement. The city’s action, it added, was “a slap in the face.”

Newton, a suburb of Boston known for liberal politics, pricey real estate and highly regarded schools, is made up of nine “villages,” each with its own identity. Nonantum has long been a neighborhood where immigrants settle. Irish and French Canadians came in the first half of the 19th century, followed by Italian and Jewish immigrants in the 1880s, said Jordan Lee Wagner, a longtime resident who has studied local history.