The A1 between Grantham and Newark is closed this morning (Wednesday) after a lorry believed to have been carrying gas canisters caught fire.
The lorry was in collision with a van near to Claypole, causing a blaze which led a plume of smoke to obscure both carriageways.
Both carriageways were closed to traffic at 5.30am today, and remain closed.
A Nottinghamshire Police spokesman said emergency services are at the scene dealing with the flames and assessing if there have been any injuries.
Diversions are in place but motorists are being asked to avoid the area, where possible.
If you saw the crash contact Nottinghamshire Police on 101, quoting incident 115 of 19 June 2013, or call Crimestoppers anonymously on 0800 555 111.