The boy is believed to come from the local area and has not yet been named. He is said to have been in the sea just after 4pm this afternoon with a friend when he disappeared.
Sussex Police began searching their area assisted by the local coastguard and other emergency services around the West Beach area of Newhaven.
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Friday morning's forecast for the west of the region
Friday morning's forecast for the east of the region
Surrey Heath MP Michael Gove has confirmed he will stand for leadership of the Conservative party - taking on Maidenhead MP Theresa May