"Asbestos has not been confirmed at the site" said South Wales Fire & Rescue Service.
"However if asbestos is confirmed, this does not pose a safety risk to the public as heavy rainfall and water from firefighting will prevent the asbestos from spreading"
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A decent start to the day with sunny spells. Breezy in the west and feeling noticeably cooler.
Tributes have been paid after two Matalan employees were allegedly stabbed to death near the city centre store where they worked.
A damp start to the night with heavy rain spreading southwards. It will clear by the early hours to leave a dry start tomorrow.