It took over two hours to get the blaze under control.
An Offaly councillor suspects anti-social behaviour is behind a major fire that broke out last night.
The blaze - at the rear of the old Tesco building in Edenderry - took two hours to get under control.
Two units from Edenderry Fire Service attended the scene shortly after 8.20.
Offaly Fire Service says the fire had been burning for a long time before they were alerted and had generated a huge volume of smoke.
Crews left the scene at 11.50.
The building is already due to be demolished next month, with a new library and arts centre to be built in its place.
Local Fine Gael councillor Noel Cribbin says it's fortunate no one was injured in the incident:
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