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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Three elderly people are being treated for the effects of smoke inhalation following fire at a nursing home in Denbighshire
A few showers possible, but these tending to fade. Cloud will break up allowing a frost to form. Some patchy mist and fog may also develop.
The 48-year-old lecturer was taken to the University Hospital of Wales, Cardiff, where he sadly died.