An RAF search and rescue helicopter and three RNLI lifeboats are searching off the coast of Harwich after getting reports that two people had come off a ferry.
Then RNLI says it happened about a mile off the Harwich coast, as the ferry was heading outbound.
Also helping in the search are tug boats and other vessels that were in the area at the time.
It happened just before 10am this morning.
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Warm sunny spells today remaining dry
Remaining dry with warm sunny spells on Monday.