The M1 motorway was tonight forced close in both directions because of a chemical fire, causing "significant delays" to motorists.
Drivers and nearby residents were warned to shut their windows because of the smoke caused by the fire which closed the motorway between junctions 26 and 28 in Nottinghamshire.
Diversions were in place around the closed section, which ran from Nuthall to the south (Junction 26) and Pinxton to the north (Junction 28).
There were long queues in both directions, and drivers were told their journeys would take at least half an hour longer than usual.
A Highways Agency spokesman said: "At the moment there are significant delays of about 30 minutes over and above the normal journey time.
"We are working very closely with the police and fire services."
Nottinghamshire Police said the blaze involved chemicals at an industrial estate in Park Lane, Kirkby-in-Ashfield.
The immediate area was evacuated and a cordon put in place.
People living in the vicinity, including Annesley Woodhouse, Kirkby Woodhouse, Kirkby-in-Ashfield and Selston, were advised to remain inside with windows and doors shut.