A coastguard helicopter and three lifeboat crews are currently searching off the Yarmouth coast following reports that a person might be missing.
Emergency services were called at noon on Sunday after a member of the public spotted a black rubber ring floating out into the sea north of Britannia Pier.
Two lifeboats from Gorleston and one from Caister have been launched to assist with the incident and a coastguard helicopter from Humberside is also searching the area.
A spokesman for the National Coast Watch station in Gorleston said: "A possible missing person incident has been declared after a member of the public reported seeing a black rubber ring floating in the sea moving towards the wind farms.
"The search is ongoing."
An eyewitness at the scene has said they can see four lifeboats at sea near a large ship.
The current is also reportedly strong today with high winds as well.
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