News: the Scottish Fire and Rescue Service has saved most of the structure and "the majority of its contents" but is still working to extinguish the fire that ripped through the Mackintosh building earlier today.

In a statement released this evening, the fire service said that its crews were still working to fully extinguish the fire and save work inside the building.

"Firefighters battling the blaze at the iconic Macintosh Building in Glasgow City Centre have prevented the destruction of both the structure and the majority of its contents," said the statement. "Scottish Fire and Rescue Service crews are continuing work to fully extinguish the fire and save artworks."

"More than 90 per cent of the structure is viable," it said, adding that up to 70 per cent of the contents of the building had also been saved.

The fire broke out at lunchtime today at the Scottish art school building designed by Charles Rennie Mackintosh. It is thought to have started in the basement before travelling up the west side of the building and across the roof.

Assistant chief officer Dave Boyle said: "While the priority from the outset was to save life we have also been working closely with Glasgow School of Art staff to ensure firefighters conducted an effective salvage operation."

"We are of course very conscious the Mackintosh is a world renowned building that is a key feature of this great city, and that the artworks it stores are not only valuable but also cherished."

"We are acutely aware this period is the culmination of years of endeavour for students and that their irreplaceable work is inside the Macintosh."

Read tributes to the building from architects including Steven Holl, who described the fire as "unbelievably tragic".

Update: Saturday 24 May

In an official statement released today, the Glasgow School of Art has said that the "iconic and unique" Mackintosh library has been lost in the fire.

"This is an enormous blow and we are understandably devastated," said Muriel Gray, chair of the school's board of trustees.

"But the most amazing, almost miraculous news is that the majority of the building is still intact. Due to one of the most astonishingly intelligent and professional pieces of strategy by the fire services, they succeeded in protecting the vast majority of the building, apparently by forming a human wall of fire-fighters up the west end of the main staircase and containing the fire."

"After ensuring no lives were in peril they displayed an impressive understanding of the precious nature of the building, and due to their careful and meticulous handling of each developing situation the damage is considerably less than we dreaded," said Gray. "We have run out of words with which to thank them, but the school has most certainly gained a new gallery of heroes."

She added that many students had lost some or all of their work, but others had not and that curators and academic staff would be entering the building "in the next few days" to assess what could be salvaged.

"The joy that our archives are safe combines with the delight in seeing most of our beloved building bruised and battered but most certainly not destroyed," said Gray.

"As for the library, Mackintosh was not famous for working in precious materials. It was his vision that was precious and we are confident that we can recreate what was lost as faithfully as possible."

She added that the school's immediate concern was the welfare of the students – many of whom had been due to hand in their final projects when the fire broke out yesterday – and the impending graduation.

Images of the fire taken on Friday 23 May are by Paulina Brozek.