THE cause behind an explosion which left roofs at the Royal Oak Industrial Estate in Daventry peppered with holes, is being investigated.
A piece of carbide, described as similar to steel but quite lightweight, was launched into the air and through the roof at General Carbide on Monday last week.
Forensic experts are investigating the cause.
The explosion caused holes at General Carbide and other neighbouring businesses with no estimate yet revealed for how much the repairs will cost.
Operations manager Mel Knowles said: “There has obviously been an accident and we all want to know what the cause of it is.”
No one was injured in the incident.