The New York police this week broke up a sprawling family-run network of drug dealers, according to the acting district attorney for Staten Island, who said the ring was run by two stepbrothers whose operation helped fuel an explosion of heroin use in the borough.

Fourteen people were indicted on a range of crimes including criminal sale of a controlled substance, criminal possession of a controlled substance and conspiracy. Twelve of the defendants were arrested on Wednesday while the remaining two were being sought by the Police Department.

“This 77-count indictment details how eight individuals conspired to distribute and sell heroin to a part of the Staten Island community that has been decimated by drug abuse and made money feeding those deadly addictions,” the acting district attorney, Daniel L. Master Jr., said in a statement released on Thursday. “The remaining six individuals are charged on five separate indictments also accusing them of dealing narcotics that fueled the drug epidemic which has impacted so many of our residents.”

The drug ring sold heroin on Staten Island but had arms in the Bronx, Brooklyn and Yonkers, as well, where many of its primary architects lived, Mr. Master said.