Defence officials examined a report of a UFO seen over Tonbridge last year, the latest documents released by the Government reveal.
The Ministry of Defence releases details of the sightings of suspected alien ships each year.
Amongst the reports from 2008 released last week was details of a sighting in the town at 12.55am on June 5.
"An object was flying around in circles at aeroplane level and sounded like an industrial train," the description of the sighting read. "There was a strange flashing on the object."
Just over three weeks later on June 28, a further sighting was reported, with the location specified only as Kent.
A statement accompanying the release of the details said the ministry examines the reports "solely" to establish whether the country's airspace has been compromised by "hostile or unauthorised military activity".
For more on this story, see this Friday's Tonbridge edition of the Kent and Sussex Courier.