Inspectors from the Health and Safety Executive (HSE) are at the scene of an incident at the Royal estate at Sandringham.
A spokesman for the HSE said:
No formal investigation has been launched, but we do have inspectors at the scene with police who are making initial enquiries.
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It's going to be a cloudy afternoon with the chance of the odd shower. Feeling cold. Highs of 6 degrees C.
An investigation is underway after a horse and pony sanctuary burnt down in Norwich.
It will be a generally cloudy day. Some bright or sunny spells are possible during the morning.