An investigation has begun to find how a "significant fire" at a factory in Wiltshire started.
Fire crews spent eight hours tackling the blaze after being called to the Apetito food factory, on the Canal Road Industrial Estate, on Monday afternoon.
The fire damaged a 40m (131ft) building used for packaging meals for care homes, hospitals and local authorities.
Adjoining buildings were evacuated and nearby residents told to keep windows closed.
At the height of the blaze, eight crews were at the scene and the fire created a plume of thick black smoke.
A Wiltshire Fire and Rescue Service spokesman said: "Wiltshire Council carried out air quality monitoring to check there was no risk to local people.
"This testing showed no concerns about particulate pollution and the advice to keep doors and windows closed has been lifted."