Andy Furey is the National Officer for Communication Workers Union, which represents staff working in Crown Post Offices.
He told ITV News: "A Welsh town like Holywell needs a Crown Post Office. If we lose it, this could be the death knell for the high street in Holywell."
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The teenager, who cannot be named for legal reasons, appeared in court to plead guilty to perverting the course of justice.
Farmer Gareth Wyn Jones is hoping for a festive online hit with footage of sheepdog Cap rounding up sheep.
It is expected to remain wet and windy for the rest of today, overnight and tomorrow. Conditions improving on Christmas Eve