Three men and a woman were awaiting arraignment Thursday on drug-possession charges after a raid Wednesday at the West 43rd Street building.
The drug ring rented a $3,800-a-month, duplex apartment two weeks ago from an apparently unsuspecting landlord, Brennan's office said. Officials with the company that manages the building - where rental listings boast hardwood floors and exposed brick walls - didn't immediately return a call Thursday. The building is about two blocks west of Times Square.
"If our investigators were surprised by the location, you can only imagine the shock of neighbors, commuters and theatergoers," Brennan said in a release.
The New York City Special Narcotics Prosecutor's office says investigators found 28 pounds of heroin - worth about $6.5 million - 250,000 small envelopes, and workers busily packing the drug up for sale.
Investigators had the building under surveillance for the past several days. On Wednesday, they saw someone exit the apartment building with a large plastic garbage bag and place it in a black BMW. The driver of the car attempted to speed off as investigators identified themselves and approached the car, authorities said. His escape was blocked by traffic at the corner of 43rd Street and 10th Avenue, where investigators arrested the driver.
Investigators said the garbage bag contained refuse from heroin production, including damaged "glassine" envelopes and other packaging material.
Investigators then went inside the apartment building to secure the heroin mill. Officials said surprised mill workers had been busily packing heroin into user-ready "glassine" envelopes in the ground-floor, duplex apartment.
Two workers allegedly tried to escape, but they were arrested along with one other person.
When they searched the apartment, investigators found piles of loose heroin, bundles of cash, coffee grinders used to dilute the drug and glassine envelopes stamped with underground brand names such as King Kong and 95 South, an apparent reference to Interstate 95, authorities said.
Some information from The Associated Press.