With lots of attention being drawn lately to the overdose of Dash Snow and the strung-out gutter punks in Williamsburg, DEA agents are confirming just what you'd expect—cheaper, more potent heroin is majorly on the rise around the Big Apple. One addiction specialist at Flushing Hospital says he's seen the number of addicts there quadruple over the last decade. The News took a closer look inside the Bronx drug dens that were part of a massive bust over July 4th weekend, spots where each kilo of heroin is broken into 30,000 tiny glassine envelopes, many of which were stuffed into Build-a-Bears. The home base of leader Jeffrey Alba's operation was "a poisonous death mill” inside a non-descript residential building on Broadway in Riverdale, just across from the baseball diamond of Kelly Field. Authorities say that they hadn't encountered an operation of this scope since heroin's heyday in the '70s, but now these are no longer covering small territories around town. An agent tells the News, "This [Riverdale] group was like a corporation, supplying the whole metropolitan area, Long Island, New Jersey."