A file photo of a UFO. Photograph:( Twitter )
The Pentagon report detailed biological effects of UFO sightings on humans. It pointed at 42 cases in which humans suffered injuries after alleged encounters with 'anomalous vehicles'.
The Pentagon declassified over 1,500 pages from Advanced Aviation Threat Identification Program (AATIP).
The AATIP programme was closed in 2012. It was made available after a request for a copy by a British newspaper. The report was released by the US Defense Intelligence Agency (DIA).
The report detailed biological effects of UFO sightings on humans in the form of paranormal experiences. However, the DIA held back some portion of the document due to privacy concerns.
The information was released under the Freedom of Information Act (FOIA) request. The AATIP programme ran from 2007 to 2012, reports say.
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The report said Americans suffered from radiation burns including brain and nervous system damage and bizarrely even "unaccounted for pregnancy". It described alleged injuries to "human observers by anomalous advanced aerospace systems" in a collection from March 2010 which it said was a "threat to United States interests".
It pointed at 42 cases in which humans suffered injuries after alleged encounters with "anomalous vehicles" meaning UFOs as people were exposed to condictions related to electromagnetic radiation with some allegedly inflicted by "energy related propulsion systems."
The report stated cases of nerve damage, heart palpitations and headaches after coming into contact with anomalous vehicles.
The report also allegedly contains biological effects of UFO sightings on humans between 1873 and 1994 which was compiled by the Mutual UFO Network (MUFON). It includes "apparent abduction", paralysis and experiences related to teleportation and telepathy.
(With inputs from Agencies)