Mid and West Wales Fire and Rescue Service says 11 of its crews are continuing to fight the fire at the National Library of Wales.
It is advising people "to stay away for safety."
This video - from viewer Edward Mulgrew - shows firefighters pumping water onto the library roof earlier.
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ITV News can reveal the number of potential buyers for Tata's steel business in the UK is more than double the previously known total.
As the weather settles at this time of year it is not the best of news if you suffer with hay fever!
Continental air dominates, and that means the next few days are looking warm and sunny! Enjoy!