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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In this today's Newsweek Wales, Carl talks about cancer survival rates in Wales and the search for volunteers to train guide dog puppies.
It'll be brighter today with some lingering blustery showers. This evening it'll be colder under clear skies, with isolated showers.
Gareth Bale put any domestic troubles behind him as he starred in Wales' emphatic 3-0 win over Israel in Haifa.