ITV News understands that the owners of the Unity Mine in Neath are filing for administration.
Around 200 people currently work at the site.
Local AM, Gwenda Thomas, told us: "It is extremely regrettable that Unity mine has gone into administration."
I sincerely hope that the administrators can find new owners for the mine, and preserve the miners’ jobs and the future of the apprentices. Welsh Government officials continue to be in discussion with the mine.
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A wet start to the week with rain for most of us this morning. Things should brighten up this afternoon.
Two people have died after being involved in separate lightning strikes in Wales' Brecon Beacons today.
Any lingering showers will ease this evening, to leave a dry night with plenty of clear spells. Minimum temperature 11 deg C (52 deg F).