South Wales Fire Service says the site of a serious fire on the Glyndwr Industrial Estate in Aberbeeg on Tuesday is now safe enough for investigations to begin.
The site is still smoking, and locals are still being warned to keep doors and windows shut and minimise the time they spend outside.
Meanwhile, Environment Agency Wales officers confirm that there has been no environmental impact on the River Ebbw, and the excess water from tackling the blaze is safely contained on the site.
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Some bright spells this afternoon, with outbreaks of rain. Top temperature 15°C.
It's judgement day at the Millennium Stadium as Cardiff Blues take on the Ospreys and the Newport Gwent Dragons face the Scarlets.
Showers expected throughout the day especially in the north. Drier and brighter elsewhere but cooler than in recent days.