Nearly 200 children and teachers were evacuated from an Easter Ross primary school after a fire broke out at a nearby factory in Invergordon.
A full investigation is now under way into the cause of the outbreak.
There were no injuries.
The fire broke out just before midday on Monday at the Kirker Europe factory on the Castle Avenue Industrial Estate.
Twenty-three staff were evacuated from the nail-polish factory.
Emergency services attended, including a decontamination unit. The fire was contained to one area of the building and was quickly brought under control.
Fire officials said the incident could have had serious consequences.
Ashley Dey, group manager, Highland and Islands Fire & Rescue, said: "All 179 pupils and their teachers at neighbouring South Lodge Primary School were moved to the edge of playing fields before being sent home."
Another 20 employees and customers from an adjacent building were also evacuated as a precaution.
A Northern Constabulary spokesman said: "The headteacher said that at no time were pupils exposed to any fumes or any danger and that the action taken was purely precautionary."
While the investigation begins, it is unclear whether production will be affected at the factory.
Employees have been asked to return to work on Tuesday to re-assess the situation.
