The United States Department of Agriculture has released a number of files about alleged alien and UFO activity on land managed by the US Forest Service, including details of the outlandish allegation.
The US Forest Service data was obtained by John Greenewald, founder of The Black Vault website, who obtains and publishes former confidential official data on aliens and UFOs.
Records of the service's Southwestern Region office in Albuquerque, New Mexico, detail a bizarre call from an alleged witness to the construction of an alien base in the Tonto National Forest, near Phoenix, Arizona.
An email was sent by the department to all rangers on December 30 2013, detailing the extraordinary encounter.
The email said: "David received a call this morning at the front desk from a male caller reporting the construction of a secret government installation upstream from the Salt River Canyon past Pinal Creek (Upstream from Roosevelt Lake).
"Aliens and at least one detached head are involved.
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