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
Police have named a teenage boy who died after a stabbing in Northampton.
A few heavy, thundery showers may continue to affect the west, but mainly dry and fine in the east with some late sunshine before dusk.
Carnival goers shrugged off the the threat of thunderstorms as they took to the streets for Luton’s annual festival.