South Wales Police says the A465 is closed between Aberdulais and Resolven, after a serious crash.
Diversions are in place via the B4242.
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A Yellow Warning has been issued by the Met Office as gale force winds and showery rain affect areas across Wales.
Welcome to the Newsweek Quiz - where we'll be testing your knowledge from the last seven days of news here in Wales.
A 9pm watershed ban on adverts that market junk food to children should be introduced, Wales' Health Minister has said.