The documents include reports of strange lights in the sky or possible spaceships hovering over the Houses of Parliament, Stonehenge and a less hallowed tourist destination, Blackpool Pier in the Lancashire seaside resort.
One email came from an observer who reported not noticing UFOs over Stonehenge but spotting them later in digital photographs taken at the Neolithic monument.
"I thought that I would send you these digital photos because they were taken a couple of years ago at Stonehenge of all places; so, possibly significant," the photographer said.
The ministry shut down the UFO desk in 2009, announcing it served "no defense purpose." Curiously, the ministry received 420 reports of UFOs and 97 requests for information under the freedom of information act, up from about 150 reports a year in earlier years.
One expert suggested the 2009 increase was a measure of the fad for releasing Chinese lanterns at weddings and other festive occasions and not an increase in extraterrestrial activity.
"Many of the sighting accounts -- such as formations of orange lights moving slowly across the sky -- describe the appearance of Chinese lanterns even though people did not recognize them at the time," David Clarke, author of "The UFO Files," told the Mirror.