Because the drugs have legal medical uses, they carry less of a stigma than illegal narcotics. After they were arrested, some of the sellers claimed they didn't know what they were doing was a crime. But investigators don't buy it.
"You'd have to be living under a rock to not know it's illegal," Brennan said.
Brennan's office reached out to San Francisco-based Craigslist earlier this week to try to get its cooperation in finding ways to discourage the Internet marketing. A Craigslist spokeswoman had no comment Thursday.
The undercover investigators began answering Craigslist ads late last year. By the time they were done, they had made 63 buys - about $19,000 in pills and $10,400 in cocaine.
One ad was placed by a self-described "friendly NYU student." It offered "pain and anxiety relief." Just in case there was any confusion, it signed off with "perc roxy." And a smiley face.
A criminal complaint accused Anthony Vargas - the Manhattan man who politely asked police not to respond to his ad - of meeting the same undercover officer four times over the summer near Union Square to sell dozens of oxycodone pills. Vargas, 40, was sentenced to nine months in jail on Wednesday after pleading guilty to criminal sale of a controlled substance, prosecutors said.
Despite the enforcement effort, the advertising continued unabated on Thursday.
One posting from someone in New York City read: "Hello ladies and gentleman. If your in pain and need assistance look no further. I've got 30 (mg) ways to help!! . . . Not affiliated with any sort of law enforcement? If ALL of these pertain to you, email me with what your looking for (quantity) and we will work it out."