There is a word that local residents and workers use to describe a group of drug users whose presence they say has grown around a busy Brooklyn transit hub: zombies. What was once a few familiar faces has turned into a tribe of strangers, walking around, staggering and looking lost, in the throes, it is believed, of the ill effects of K2, a synthetic drug that officials in New York have been working hard to eradicate.

The problem in the neighborhood has gotten to be such that a manager of an urban farm nearby, tired of the smoke wafting onto the property, posted two hand-painted wooden signs with a simple message: “No Smoking K2.”

On Tuesday, the longstanding problem became a local crisis on this gritty patch, on the border of two developing neighborhoods, Bedford-Stuyvesant and Bushwick. In the area around the subway station at Myrtle Avenue and Broadway, emergency workers transported 33 people who were suspected of overdosing on K2 to hospitals, the police said. The powerful drug, also known as Spice or synthetic marijuana, has grown in popularity in recent years despite public warnings.