A worker on the Sandringham Royal estate is in a criticial condition at Addenbrooke's after being rescued from a lake.
The man, in his 30s, was rescued from Lower Lake and taken to the Cambridgeshire hospital by air ambulance. He is in a critical but stable condition.
Police and the Health and Safety Executive are carrying out a joint investigation into the incident.
Emergency services were called to the Norfolk retreat at about 1.30pm yesterday after reports that an estate worker, in his 30s, had fallen into the Lower Lake while operating a ride-on lawn mower.
It is understood the Queen was at Sandringham on a private visit less than an hour later.
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The votes are being counted in 22 councils across the Anglia region in the biggest test of political opinion since the General Election.
Clear skies overnight but remaining frost-free. Another sunny day tomorrow and increasingly warm as we head towards the weekend.
Voting is taking place across the Anglia region in the biggest test of political opinion since the General Election in May 2015.