Update: The road is now closed at A46 Haddington/Aubourn. The A46 at Whisby to Pennells has been re-opened but traffic is moving slowly.
The A46 between Whisby roundabout and Pennells roundabout has been closed in both directions due to a van fire.
A spokesperson for Lincolnshire Fire & Rescue said one crew are on site dealing with a vehicle fire.
The incident was reported to police at 3.15pm this afternoon.