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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The family of a teenager who was stabbed to death as he walked home from college in Chelmsford say they are inconsolable.
Dry and chilly overnight. Winds strengthening Sunday and becoming milder.
Dry with some sunshine but a cold wind.