The unmanned planes – some of which may have been designed to kill terror suspects – are being launched from locations in 20 states.
Most of the active drones are deployed from military installations, enforcement agencies and border patrol teams, according to the Federal Aviation Authority.
But, astonishingly, 19 universities and colleges are also registered as owners of what are officially known as unmanned aerial vehicles.
It is thought that many of institutions, which include Cornell, the University of Colorado, Georgia Tech, and Eastern Gateway Community College, are developing drone technology.
As well as active locations, the FAA also revealed 16 sites where licences to use spy planes have expired and four where authorisations have been disapproved, such as Otter Tail County, Minnesota.
Its website hosts an interactive map that allows the user to zoom in to the area around where they live to see if any sites are nearby.
However, the FAA is yet to reveal what kinds of drones might be based at any of these locations.
The agency says it will release this data later.
Most of the drones are likely to be small craft, such as the Draganflyer X8, which can carry a payload of only 2.2lb.
Police, border patrols and environmental agencies, such as the National Oceanic and Atmospheric Administration (NOAA), could use for them effectively.
While few would object to vast open areas being monitored for wildfires, there are fears of privacy violations if drones are used to spy over cities.
The FAA released two lists of public and private entities that have applied for authorisations to fly drones domestically.
Certificates of Authorizations (COAs), issued to public entities like police departments, are active in 42 locations, expired in 16 and disapproved in four.
Special Airworthiness Certificates (SACs), issued to private drone manufacturers, are active in 21 locations and not active in 17.
Among the other unanswered questions, however, are is exactly how many drones each registered user owns.
But this information does not reveal how many are owned, for example, by Miami Dade Police Department.
While the use of drones in the U.S. is little known, American operations overseas have been well documented.
As well as high-profile terrorists, campaigners claim hundreds of innocent civilians have been killed in the border regions of Pakistan, where they are most active.
SO WHICH PUBLIC ENTITIES ARE REGISTERED OWNERS OF DRONES? FULL LIST REVEALED HERE
Arlington Police Department Mississippi State University
U.S. Army U.S. Navy
City of Herington, Kansas New Mexico Tech
City of North Little Rock, AR Police Department Ogden Police Department
DARPA (Defense Advanced Research Projects Agency) Ohio University
DHS (Department of Homeland Security) / CBP (Customs and Border Protection) Orange County Sheriff’s Office
DHS (Department of Homeland Security) / Science and Technology Polk County Sheriff’s Office
DOE (Department of Energy) – Idaho National Laboratory Seattle Police Dept
Department of Agriculture – Agricultural Research Service Texas A&M University Corpus Christi
Department of the Interior – National Business Center/Aviation Management Directorate Texas A&M University – TEES
Eastern Gateway Community College University of Alaska Fairbanks
Texas State University University of Colorado
FBI (Federal Bureau of Investigation) University of Connecticut
Gadsden Police Department
Georgia Tech Research Institute University of Florida
Kansas State University University of North Dakota
USMC (United States Marine Corps)
Mesa County Sheriff’s Office
Miami-Dade Police Department Utah State University
Middle Tennessee State University Virginia Polytechnic Institute and State University
New Mexico State University Physical Sciences Laboratory (NMSU-PSL) Washington State Department of Transportation
NASA (National Aeronautics and Space Administration)
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