Milford Haven Coastguard says an operation is underway to rescue a Portuguese seaman with serious head injuries in rough seas off the coast of Pembrokeshire.
Warship HMS Echo, which was passing nearby, is trying to provide shelter to calm the water so that the injured man can be winched to safety.
A rescue helicopter from RAF Chivenor and Angle Lifeboat are also involved in the rescue around 18 miles west of St Ann's Head.
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Aaron Ramsey has told his English team-mates at Arsenal to beware Wales overtaking them in the FIFA rankings.
Plenty of fine dry weather to come today and prolonged spells of sunshine. A cool easterly breeze will take the edge off the temperatures.
The three-day event in the Welsh capital is expected to attract more than 20,000 visitors.