While not explicitly naming the Top Gear program or The Stig himself, the BBC did have a few things to say about the incident. The gold Lamborghini Murcielago was being driven by "a professional," who escaped unharmed. The BBC also confirmed that the accident occurred during "a test run on a rain-soaked runway in Dunsfold Park, Surrey."
That location happens to be where Top Gear does most of its testing. A witness related that it appeared as though the driver just lost control in the bad weather, and that the Lambo was "spinning rapidly before skidding off the track and coming to a halt in a field. It looked pretty bashed up."
[Source: The Daily Mirror]