British UFO hotline shut down, The Ministry of Defence closed its UFO desk because it served "no defence purpose" and was taking staff away from "more valuable defence-related activities", newly released files show.
The desk was closed in December 2009 despite a surge in reported sightings.
The disclosure came in National Archives files relating to reports of UFOs - Unidentified Flying Objects - between 2007 and November 2009.
They show UFOs were reported at several UK landmarks, including Stonehenge.
'No benefit'
The latest tranche of declassified files covers the final two years of work carried out by the MoD's UFO desk.
The 25 files include reports alleging contact with aliens and UFO sightings near UK landmarks, and detail the decision to close the MoD's dedicated desk and "hotline".
In a briefing for the then defence minister, Bob Ainsworth, in November 2009 a civil servant, Carl Mantell of the RAF's Air Command, suggested the MoD should try to significantly reduce the UFO work. He said it was "consuming increasing resource, but produces no valuable defence output".
He told Mr Ainsworth that in more than 50 years, "no UFO sighting reported to [the MoD] has ever revealed anything to suggest an extra-terrestrial presence or military threat to the UK".
His memo said there was "no defence benefit" in the recording, collating, analysis or investigation of the sightings, adding: "The level of resources diverted to this task is increasing in response to a recent upsurge in reported sightings, diverting staff from more valuable defence-related activities."
An official MoD statement from the time said the department had "no opinion on the existence or otherwise of extra-terrestrial life".
It went on: "In order to make best use of defence resources, we have decided that from December 1 2009 the dedicated UFO hotline answer-phone service and email address will be withdrawn. [The] MoD will no longer respond to reported UFO sightings or investigate them."