“Classified documents… show a little-known FBI organization, the Data Intercept Technology Unit, is apparently in charge of obtaining information … and then providing the data to the NSA.”
Searching “Data Intercept Technology Unit” can be quite instructive.
The FBI is Helping the NSA Spy, but Senators Don't Want to Know About It | Killer Apps.
Dr. Christian W. Erickson, Ph.D. 