The Brooklyn neighborhood may be rapidly gentrifying in some places, where trendy bars cater to displaced Manhattanites and apartment sales have approached seven figures.

Yet there are no million-dollar homes in the shadow of the Marcy Houses, along Flushing Avenue in Bedford-Stuyvesant’s crime-troubled northern edge. And when gunfire erupted on Saturday evening, there were few residents who did not recognize the sound, or shake their heads at its deadly result:

An 18-year-old man dead on the scalding summer pavement; a 13-year-old boy critically wounded by a bullet to the neck; and two other boys, 14 and 15, each hit in the leg by bullets.

“The only thing that changes is the faces,” Chuck Xavier, 47, a lifelong resident of the Marcy Houses, said. “It’s sad.”

By Sunday, detectives had narrowed in on a possible suspect who witnesses said fired a semiautomatic pistol at the teenagers as they stood together in front of 472 Marcy Avenue. The cause of the shooting, the police said, appeared to be an increasingly familiar one — a dispute between gangs from rival housing projects.