Emergency services are dealing with an overturned lorry which blocked the entire southbound carriageway of the A1 near Grantham.
The incident was reported to Lincolnshire Police at around midday on Wednesday.
Long delays being reported on the A1 between the B6326 near Newark-on-Trent and the B1174 near Grantham.
This was a result of a collision which saw a heavy goods vehicle overturn and block the southbound carriageway, as well as damaging the central barriers between northbound and southbound lanes.
National Highways began clearing the traffic in the area from the back of the queue at around 2.30pm, with delays expected on the road until around 5.30pm this evening.
The road will remain closed southbound until the area is cleared and it is safe for vehicles to continue on the route, with highways thanking road users for their patience.
There have been no reports of injuries at the time of publication.
The Lincs & Notts Air Ambulance was deployed to the scene, and eyewitnesses say it left without a patient inside.
Road users are advised to follow the Hollow Diamond diversion symbol on road signs.
- Exit the A1 southbound at the A46/A17 Newark Junction and turn left onto the A46 (south) heading towards the A1/A46 Brownhills roundabout.
- Continue straight over at the roundabout and travel along the A46 to A46/A617/A616 Cattle Market roundabout.
- Continue straight over the roundabout along the A46 until Farndon roundabout, then turn right and travel along the A46 through the villages of Farndon and East Stoke until the A46/A6097 Margidunum roundabout.
- Continue straight over at the roundabout (high loads are circumvented through Bingham), until the A46/A52 Saxondale Island.
- Turn left (east) onto the A52 and continue for approximately 19km until the A52/A1 Barrowby southbound junction then re-join the A1 southbound.
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