Arwel Jones from the National Library of Wales told ITV News that he is hoping that the damage will be limited - "the most valuable stuff is housed in purpose-built cells at the very bottom of the library, and this fire is at the very top."
He admitted to concern that the damage from water pumped onto the building by firefighters would be as bad as the fire damage.
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A group of glamorous grannies in north Wales are baring all in the name of charity with their own calendar.
Heavy rain likely across some of the hills and western slopes in particular.
Kyle Vaughan was last seen on 30th December 2012. His parents Alan and Mary say all they want for Christmas is to lay him to rest.