Update: Mystery of UFOs over Norfolk solved? Now with a video!
Visitors from another planet or, rather more likely, something far more down to earth?
Whatever the explanation, there were more reports of unusual 'flashing lights' over Norfolk last night.
People took to social media website Twitter to report lights between Norwich and Fakenham, at Cromer and in North Suffolk.
One reader, who was watching from Cley beach, got in touch to ask if anybody else had spotted the lights.
He said: 'Around every 20 seconds there was a double power flash. At first I thought It was lightning, but it was just too evenly timed and in the same spot for hours.'
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David Auton, who is on holiday in north Norfolk, reported seeing bright flashes of light near Mundesley, Bacton and Happisburgh while walking his dog at around 10.30pm.
'At first I thought it was an explosion on a ship out at sea because it seemed to come from the grounds upwards and was always in the same place,' he said. 'Then I thought it was lightening but the weather conditions weren't right for lightening. It was certainly very unusual.'
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Shane Patel, from Norwich, emailed us to say he had asked friends on Facebook about the phenomenon and received a number of reponses.
He said: 'I saw that the flashes were random, in size and timings, and only appeared to be emerging from clouds.
'After the one from my bedroom stopped, flashes were seen in Oulton Broad and Lowestoft, before travelling back to Norwich. Lots of people freaked out!'
Robin Spencer emailed us the video clip used here and said: 'Caught it on video. The clip doesn't really do it justice but it was quite spectacular and lit up the whole sky. I still think it was lightning but it was strange how regular it was and that there was no thunder.'
Dan Holley, from University of East Anglia-based forecasters Weatherquest, said those who suspected sheet lightning were probably correct.
He said: 'There were a lot of offshore storms last night, so it probably was sheet lightning. And when the skies are clear you can see that from quite a long way inland.'
Last month, we reported how readers had reported bright white and blue lights off the coast of Cromer and a 'bright, golden light' hovering over the sea east of Southtown in Great Yarmouth.
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