"The crash was so dramatic," a witness told the Daily Mail. "He hit one wall and spun round 360 degrees before bouncing off the other.
"There was an enormous bang and sparks everywhere. I was worried the car was going to explode."
Radcliffe is actually a racer himself, having won races in the British GT Championship and the GT Cup where he often pilots GT3 machinery.
"What exactly happened is to be a mystery," another source said. "But rumours go; it accelerated in the tunnel and lost control to the rear hit the wall and spun it. But the main thing is that the owner is okay. Cars can be repaired, people's lives can't."
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