The man was working inside the trench in the village of Letterston when the sides caved in. A specialist rescue crew is at the scene, along with firemen and paramedics.
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Not a bad start to the weekend, bright spells and showers for most of us.
None of the people onboard the boat had been wearing a lifejacket. They were spotted clinging to the hull of their upturned boat.
Staff at seven museums in Wales are taking strike action this weekend over plans to cut their pay.