A Stanmore caterer has relived the moment she claims she spotted a UFO 24 years ago after the Ministry of Defence released secret files on paranormal sightings.
Ruth Novelli, of Bushey, said she saw the UFO at 9.45pm on April 26, in 1984, in her back garden in Belmont Lane, Stanmore.
The 61-year-old spotted the UFO after a neighbour alerted her to a strange object in the sky.
She said: "My next door neighbour knocked on my door and asked me to see what it was. I looked up and there was a light in the sky that was changing colours from pink to yellow to blue.
"It was also moving back and forth and up and down, but we weren't close enough to see it."
Mrs Novelli, who was 38 at the time, said: "My neighbour called the RAF to see whether they had anything up there and they didn't, so she called the police.
"The police blocked off the road and took pictures with a telescopic lense. I didn't know what it was. I wasn't scared, just mystified. It was there for three hours."
According to police reports at the time, an officer described the object as moving erractically and being "circular in the middle with a dome on the top and underneath".
The object appeared to be over the Borehamwood or Mill Hill area. Mrs Novelli believes that the police then followed the UFO as it moved down the M1, but they lost it when it took off at high speed.
Mrs Novelli, who co-owns Browns Cafe, in Church Road, Stanmore, has been bombarded with enquiries since the files were released. The new documents contain records from 1978 until 1987.
There have been more than 150 unexplained sightings in England the last 10 years. The last recorded sighting in Harrow was in October 2000, when a witness saw a luminous green stripe appearing in the sky at 5.50pm.
Maggie Daley, from The West of London Astronmical Society, thinks most sightings have a logical explanation.
She said: "I have never seen anything which I couldn't explain but wouldn't ridicule anyone who says they have had a close encounter of a third kind."
The space enthusiast also said that lights from aeroplanes, hovering hot air baloons, meteors burning up as they travel towards earth and bright stars were commonly mistaken for extraterrestial beings.
She said: "There used to be an illuminated air balloon which did journeys over north-west London at night. This was probably the cause for a number of UFO sightings."
Mrs Novelli has not seen anything like the object she saw in the sky again and is sceptical about what it actually was.
She said: "I don't believe or disbelieve. I'm not saying it was something from space. I'm just saying I don't know what it was."