The MOD has released once-classified files concerning reports of flying saucers, alien abductions and close encounters to the National Archives, and the Norwich case is one of the most remarkable to have occurred between 1987 and 1993.

On November 21, 1989, the distressed woman telephoned RAF Wattisham to talk about her frightening experience and a covering note provided to the MOD and Norfolk police at the time by the RAF man she spoke to described it as “one of our more unusual UFO reports”.

The woman, who did not give her name and address, said the previous night she had been walking her dog on a sports field not far from her home near Norwich.

The RAF report stated: “She was approached by a man who asked her if she would listen to what he had to say. She described the man as 5ft 9in, fair hair, with a Scandinavian type accent and dressed in a light brown garment similar to a flying suit.

“He asked her if she was aware of stories about large circular flattened areas appearing in fields of wheat, and then went on to explain that he was from another planet similar to earth and that the circles had been caused by others like him who had travelled to earth.

“He went on to explain that the purpose of their visits was friendly but that they were told not to have contact with the people of earth for fear that they might be treated as a potential threat.

“He had spoken to her because he felt it was important for contact between the two people to occur.”

The woman told the RAF man that she was “completely terrified while this was taking place” and could not remember much else about the conversation.

But the report then stated: “After about 10 minutes the man left her and she ran towards home until she heard a loud buzzing noise behind her and turned to see a large spherical object, glowing orange-white rising vertically from behind some trees which rose steadily out of sight.”

The RAF man said the conversation with the woman lasted for about an hour, followed by another 10-minute call when she rang again.

He said: “I could not get her to divulge her name or address but I believe that this was a genuine call.”

When the last batch of previously secret documents were released last summer, sightings between 1978 and 2002 included a mysterious saucer shaped object over Ashwellthorpe, a fast moving pink light over Dereham Road in Norwich and a fat “coffin-shaped” craft spotted by Norwich air traffic controllers.