UFOs had sexual encounters with humans and even left one woman pregnant, witnesses have alleged.
The wild claims were made in bombshell Pentagon documents obtained by The Sun from the Defense Intelligence Agency (DIA) as part of a huge Freedom of Information request.
The report - titled Anomalous Acute And Subacute Field Effects on Human and Biological Tissues - investigates injuries to "human observers by anomalous advanced aerospace systems".
It investigates the health impact on humans who have had paranormal experiences.
The document features a "useful database" which listed the biological effects of UFO sightings on humans and their frequency, compiled US-based civilian research agency MUFON.
This includes bizarre occurrences such as "apparent abduction", "unaccounted for pregnancy", sexual encounters, experience of telepathy and perceived teleportation.
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