Fire crews attended the blaze in Aberdeen city centre.
Police have issued an appeal after bins were set on fire and the blaze spread to a workshop in Nairn last night.
Firefighters rushed to Church Street in the town after the alarm was raised at 11.55pm.
No one was in the property and the blaze was extinguished within an hour, with fire crews using a hose reel jet, breathing apparatus and thermal imaging camera.
Police Scotland is treating the incident as wilful fireraising.
Two bins were discovered to be alight and the fire then spread to exterior panels of the workshop, which measured 10x15metres.
Sergeant Steven Maclennan said the fire was believed to have been deliberately set and they are now appealing for information.
He added: “Deliberately setting fires is inherently dangerous. You have very little control over how it may develop and what the consequences could be.
“Our enquiries are ongoing and any information, even if it was something you didn’t think was notable at the time, could be useful in helping us establish the full circumstances.”
Anyone with information is asked to contact Police Scotland on 101 or call Crimestoppers anonymously on 0800 555 111.”
