via Security – CNET News.

In September 2008 police began arresting alleged members of Dark Market, an underground Internet forum for buying and selling credit card data used for identity fraud. The sting wouldn't have been possible without the work of FBI agent J. Keith Mularski who spent two years infiltrating the group.

FBI Special Agent J. Keith Mularski spent two years posing as a cybercriminal as part of an undercover sting operation.

(Credit: U.S. Federal Bureau of Investigation)

Mularski became hacker “Master Splynter,” a play on the name of the Teenage Mutant Ninja Turtle character called “Master Splinter,” a rat who lives in New York City's sewers. He was so successful in his online disguise that he ended up running the server that hosted the Dark Market forum from his offices at the National Cyber Forensics Training Alliance in Pittsburgh.

Mularski, a supervisory special agent with the FBI's Cyber Initiative & Resource Fusion Unit, spoke about the Dark Market sting during a session at the RSA security conference last month. CNET News caught up with him this week on the telephone to find out what it was like hanging out with cybercriminals.