The Bureau mostly sent standard replies
FBI, 1966.
This is Section 10 of FBI Headquarters file 62-HQ-83894, running from 1966 to 1977. It is mostly letters from the public about UFOs and flying saucers, the Bureau's standard reply that UFOs are not the FBI's business, and enclosed saucer publications, news clippings, and a few reports of claimed sightings and contacts. By this point the replies mostly steer people toward the Air Force or other channels rather than the FBI. The main thing to take from it is that the saucer question had turned into a public mail problem more than an investigation.
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