The Welsh Ambulance Service says it was called to a crash on the A465 eastbound, between Aberdulais and Resolven, at 3.42pm.
A lorry and a van have gone down an embankment.
There is no news on casualties yet, as they are still on the scene.
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Showers will be replaced by more persistent rain this evening, with some heavy outbreaks expected. The rain will become patchier overnight.
Mary Owen has been working at the school in Old Colwyn for 46 years and still loves her job as much now as she did at the very beginning.
The latest weather forecast for Wales.