Fire crews at agricultural supplier in Swaffham
About 20 firefighters are at a fire at an agricultural supplier's industrial unit in Norfolk.
Emergency crews were called to the site near Travis Perkins in Lynn Road, Swaffham, at 18:30 GMT.
The fire service said they were concerns over pesticides, so crews were standing back until they knew which chemicals were involved.
A spokesman said there was no risk to public as smoke was blowing away from the town.