A1 motorway northbound in Hertfordshire shut following serious collision.

The A1 motorway- which connects London to Edinburgh- has been shut northbound following reports of a serious collision.

It's been closed between J1 (South Mimms) and J3 (near Hatfield).

UPDATE (11:05) - Hertfordshire police said: "For reasons unknown at this stage, a black Vauxhall Corsa was travelling northbound when it left the carriageway and collided with a tree.

"The two occupants of the vehicle sustained serious injuries and were taken to hospital for treatment.

"Officers are appealing for witnesses, information and dash cam footage."

National Highways say there's currently no ETA for reopening of the carriageway, with trapped traffic being turned around by traffic officers.

UPDATE (10:26) - Hertfordshire Police said: "We're currently dealing with a serious collision which occurred at around 7.40am this morning near Junction 2 northbound.

"It involves 1 vehicle and the road is closed."

Emergency services, including Hertfordshire police, are still on the scene.

Sergeant Luke Jenkins from the Bedfordshire, Cambridgeshire and Hertfordshire Road Policing Unit, said: “Our enquiries are continuing at this time to establish the circumstances around this collision. We are appealing for anyone who witnessed the incident, or anyone who was driving down the A1M around that time this morning who believes they may have seen the car, to please get in touch as soon as possible.

National Highways are advising affected drivers to follow this diversion route:

• Exit the A1 at J1 and take the 1st exit at Bignells Corner roundabout.
• Join the M25 at J23 anti-clockwise.
• Follow the M25 and exit at J22.
• Take the 3rd exit on the roundabout onto the A1081 towards St. Albans.
• At the next roundabout, take the 2nd exit onto the A1081 towards St. Albans.
• Follow the A1081 and take the 4th exit at the next roundabout onto the A41 (North Orbital Road) towards Hatfield.
• Follow the A414 to J3 of the A1(M) and take the second exit to re-join the A1(M) northbound.

Sergeant Luke Jenkins from the Bedfordshire, Cambridgeshire and Hertfordshire Road Policing Unit, said: “Our enquiries are continuing at this time to establish the circumstances around this collision.

"We are appealing for anyone who witnessed the incident, or anyone who was driving down the A1M around that time this morning who believes they may have seen the car, to please get in touch as soon as possible.

“If you were driving in the area around the same time and have a dash cam fitted to your vehicle, please review the footage as a matter of urgency and send through anything you think may assist with our investigation."

If you have dash cam footage in relation to the collision, upload this at: https://upload.5fdams.aetopia.net?ref=76G8M3

We'll bring you details as we get them.

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