Residents in Coleraine, Co Derry, were forced from their homes by toxic black smoke last night.
The acrid cloud descended on hundreds of homes after an Armstrong Medical Services warehouse containing medical supplies caught fire last night.
Around 80 firefighters from across the North attended the Wattstown Business Park fire.
Six hundred homes were evacuated, and people were housed in local hotels and other establishments.
Firefighters managed to save 50 per cent of the complex, but a large warehouse containing plastic medical supplies was destroyed.
There were around 20 people in the plant at the time, and fire service commander Peter O'Reilly said some of the site's 70 jobs could be put at risk.
