When mysterious objects were seen in the skies above a school oval and paddock in a small town in south east Melbourne 52 years ago, local authorities reportedly told witnesses to keep quiet.

To this day, residents and interested parties remain baffled by what took place that day, with conspiracy theories pointing to a government cover-up rather than an extra-terrestrial visit.

It was around lunchtime on Wednesday, April 6, 1966, when students and staff from Westall High School and Westall State School, in Clayton South, spilled out onto the local oval for sport.

As the students went about their exercises, hundreds of them claim to have witnessed unexplained objects flying overhead before disappearing into a nearby grassy paddock known as The Grange.

“I think we were all just stunned. They were all hovering,” Phyll Tierney, who was among the students out on the oval that day, told nine.com.au.

Ms Tierney, who was 15 at the time of the sighting, said she remembers seeing three silver disc, dish-like shaped objects with a dome at the top in the sky. She claims none of them made a sound.

“There were two others as well but they were quite a way over the other side of the oval,” she said.

Aerial photo of Eileen Road area of Westall/Clayton South in 1966. Westall Road is on left side, Spring Valley Golf Course on right side, and part of The Grange on bottom side of photo. (Supplied) (Facebook)

“It was the sort of the thing that you read about but never happened to you.”

If the sightings weren’t enough to spook the students – two were reportedly taken off in an ambulance – they were gathered in the school grounds and told to tell no one of the incident. It was shortly after that the military arrived.

“It was so covered up. We weren’t allowed to talk to the media. They told us all to go to the quadrangle, the headmaster was adamant that we’d seen nothing,” she said.

Shane Ryan, a Canberra researcher and an enthusiast of the Westall incident , backs up Ms Tierney’s claims having spoken with more than 400 people who claim to have witnessed the incident and subsequent stern visits from authorities.

“When they saw these objects they knew straight away that it wasn’t anything ordinary. It was inexplicable to them,” Mr Ryan told nine.com.au.

“They referred it to it at the time as a flying saucer, that is what it looked like to them.”

He was quick to add the description of the object didn’t mean it was extra-terrestrial, though he does believe the incident is a “UFO story”.

Government correspondence from 1966 about the incident in Westall. (Supplied) (Facebook)

“When you talk about UFO stories it is lights in the sky and one or two people seeing something unusual but this was broad daylight, witnessed by hundreds of people and seen to come down or be close to the ground,” he said.

Mr Ryan said witnesses have told him that within 20 to 30 minutes after the sightings “the military and the police were on the scene” as well as two separate fire brigades.

“One of the students was very affected by what she had seen. She was taken away,” he said.

“The civil defence organisation, the precursor to the state emergency service, was set up to help (in the event of a) major disaster or radiation leak. They were responded and came out to the Grange. It was a pretty big thing.”

However, he claims that part of this “enduring mystery” is the lack of evidence that any of the authorities were called to respond to the school oval that day.

“We still can’t find the document trail that links they services out there that day. There’s absolutely nothing,” he said.

Shane Ryan has been investigating the Westall 66 incident for the past 13 years. (Supplied) (Facebook)

“I’ve been in touch with two of the fire fighters there, one from metro fire brigade and… yes it happened they were there … but there’s no documentary evidence.

“We know that the air force was on the ground that day, they were at the school and the science teacher vividly remembers two RAAF come to his home. And yet in the official air force UFO cases that year there was no mention.”

He said he has checked the entire air force list of UFO cases for that year and the preceding and following year and there is no mention of the 1966 incident.

As well as claiming to have witnessed the objects in the sky, Ms Tierney also vividly remembers seeing the scorched earth and three identical circles in the grass at The Grange that same afternoon.

According to Mr Ryan’s research, which was used to make the 2010 documentary film, Westall 66 , she is one of 160 people to have witnessed the circles.

“We went over to the Grange as soon as school finished, we climbed through the fence. It was one of our play areas,” she said.

Witness Kevin remembers the circle as being between Fairbank Road and the pines at The Grange. (Supplied) (Facebook)

“The grass was normally about two or three foot high in this paddock and when we climbed through the fence there was three flattened spots singed around the edge. The grass was absolutely flattered. There were three swirling disc in the middle.

“It’s what we found and nothing at all could deter us from saying any different.”

Yet, in the 52 years since the incident there appear to be no answer to what happened. While Mr Ryan continues to be contacted by witnesses to this day, he is yet to find an answer to what happened.

“Seems to be that something went wrong that day at Westall that some rule or some protocol or even some law was broken that day,” Mr Ryan said.

“What I mean is that something went wrong, either of in terms of the object was never meant to have been seen, or if it was something truly exotic, not from Australia then what got broken I guess was the fact that nobody was in control that nobody could explain what people saw.

Newspaper clippings and media at the time of the 1966 incident. (Supplied) (Facebook)