I heard some Federal Protective Service units on roll call this morning report that they were participating in "Operation Shield" activities. Roll call was on 408.2 MHz here in the Portland, OR area.
A quick search of the Internet told me that Operation Shield is an ongoing program that is part of the FPS operation. Here is a link to see what they are up to:
http://www.ice.gov/doclib/pi/fps/pdf/fps_02_08_newsletter.pdf