posted on Dec, 26 2010 @ 10:26 PM
There are various devices that will accomplish this;
Portable X-ray, thermal scanner, High frequency radio scanning, specialized radar...or combination of these scanners have been used in the last decade
to provide surveillance of suspects in Hotels, Restaurants, Office, apartment and other locations by Homeland Security, FBI, CIA, and other alphabet
agencies. These are very expensive systems and are portable carried within 1-2 moderate suitcases.