It is not yet clear when the crash happened.
BBC journalist Adam Hale said no obvious signs of a crash were visible, even in daylight, to drivers using the slip road to approach the busy roundabout over the weekend.
"I was one of the potentially thousands of motorists who will have passed the scene of the accident over the weekend who could be forgiven for not noticing anything out of the ordinary," he said.
"There are a lot of trees that line that particular stretch of road that could easily obscure a car that had left the road.
"In terms of things you'd expect to see in the aftermath of a road accident - tyre marks on the road, parts of a car strewn across the way - none were clearly visible to myself or friends or family who live in the area and also travelled past the site across Saturday and Sunday."
BBC journalist Adam Hale said no obvious signs of a crash were visible, even in daylight, to drivers using the slip road to approach the busy roundabout over the weekend.
"I was one of the potentially thousands of motorists who will have passed the scene of the accident over the weekend who could be forgiven for not noticing anything out of the ordinary," he said.
"There are a lot of trees that line that particular stretch of road that could easily obscure a car that had left the road.
"In terms of things you'd expect to see in the aftermath of a road accident - tyre marks on the road, parts of a car strewn across the way - none were clearly visible to myself or friends or family who live in the area and also travelled past the site across Saturday and Sunday."

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www.bbc.co.uk