The Coastguard said it was called to a “tragic incident” on West Mersea Beach, with people being asked to stay away from the area.
Essex Police, the RNLI and the East of England Air Ambulance were also in attendance in the seaside town, near Colchester, on Wednesday evening and were seen searching the coastline and the water.
In a post on Facebook, West Mersea Coastguard Rescue Team said it had been called to a “tragic incident” on the beach and its thoughts were with the family involved.
Police have asked the public to avoid the Seaview Avenue and beach area.
“Part of the beach at the bottom of Seaview Avenue in West Mersea has been cordoned off and police are focusing their on-land inquiries on part of the sand where there are windbreakers in place.
This is a spot that gets really busy when it’s hot, being the main beach on what is seen as a pretty exclusive island on the Essex coast, south-east of Colchester.
But tonight it is busy for a different reason. There has been a huge presence of police, paramedics and water rescue workers in the area – and they remained there as it got dark.
A lifeboat could be seen launching at one point and searching the water. Police officers are also searching the shoreline with torches as the light fades.”
An RNLI spokeswoman confirmed its West Mersea lifeboat was launched earlier this evening and its lifeboat from Clacton was also sent to the emergency.
She added she did not know the nature of the incident at this stage.
The Reverend Jo Parrott said West Mersea Parish Church would be open for anyone affected.
A spokeswoman for the East Anglian Air Ambulance said it hadsent a helicopter to West Mersea, but she had no further information.
The BBC has contacted Essex Police, HM Coastguard and the East of England Ambulance Service for more details.
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