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.
More top news
Truckfest is back in Peterborough. The two day event sees thousands of people flocking to the East of England Showground.
It will be dry overnight with sunny spells tomorrow before rain and strong winds later in the evening
Anglia Weather: Mostly dry and occasionally sunny