The A17 at Asgarby near Sleaford is closed after a serious crash on the A17 on Friday afternoon.
Lincolnshire Police said as of 2pm the road is closed between Swineshead Bridge and Holdingham roundabout.
Police are advising motorists to avoid the area and to plan an alternative route.
Anyone who witnessed the collision should contact police on 101 quoting reference number 245 of June 21.
Lincolnshire Police were contacted for further information, but there was no reply by the time of publication.