Humberside Fire & Rescue Service issued a warning to motorists using a main road in the Brigg area yesterday afternoon (Friday, April 22).
It said crews from Barton, Brigg and Immingham were dealing with a large quantity of pallets on fire on the Elsham Wold Industrial Estate.
"Passing motorists on the A15 should keep vehicle windows closed," the service instructed in a social media post issued in the afternoon.
A later update from the service explained that about three tonnes of wooden pallets had been involved, with smoke damage caused to an outbuilding.