South Wales Police say 12 vehicles have been involved in a crash on the A465 between Glynneath and Hiwaun this evening.
One person has been taken to hospital with injuries not believed to be serious.
The road remains closed as emergency services work to clear the area.
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There will be plenty of sunshine and blue skies today with some warm temperatures and very high UV levels.
From Monday two Welsh households will be able to meet outside providing they socially distance and live within 5 miles of each other
Any number of people from two households in Wales will be able to meet outdoors and at a social distance, if they live in the same area.