BOSTON — Back Bay, one of the city's wealthiest and most tourist-facing neighborhoods, has become unrecognizable to residents this summer as open drug use spreads across Copley Square and the front steps of the Boston Public Library.

"Why are you turning a blind eye to the open drug use happening in Copley Square and Boston Public Library?" the neighborhood activist account Back Bay SOS wrote in an Instagram post tagging Mayor Michelle Wu this week. "Is it because the tourists are gone?" The post went viral, racking up more than 2,500 likes, nearly 70 shares, and 1,400 saves.

One Back Bay resident who stopped at the Copley Square farmers market this weekend told Back Bay SOS that "literally there are multiple people trying to find veins with openly exposed needles out. This is out of control." Photos posted by Back Bay SOS showed a person passed out on the sidewalk outside a Boylston Street storefront, a wheelchair and bedding piled beside a cardboard donation box; brightly-colored syringe caps littering a nearby curb; and a group of visibly strung-out individuals gathered on the marble steps of the BPL's Central Library, feet from Trinity Church.

The neighborhood, home to Newbury Street's luxury retail, the Copley Plaza and Fairmont Copley hotels, and multi-million-dollar brownstones, has long served as Boston's ceremonial front door for out-of-town visitors. Locals say the scene has visibly deteriorated in recent weeks — coinciding, they note, with the drop-off in summer tourism.

Back Bay SOS's most recent post also tagged Governor Maura Healey, the BPL, Trinity Church, and multiple neighborhood associations, ending with the hashtag #mayorwuwhereareyou.