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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A mainly dry day with some sunny spells in the morning, but turning cloudier during the afternoon. Feeling warm. Highs of 27 deg C.
A 54-year-old man has died and another has been taken to hospital after a group of swimmers got caught up in a riptide at a Norfolk beach.
It will be a dry and warm night with some clear spells and light winds. Lows of 15 deg C (59 deg F).