At around 1.50am on Thursday 11 June 2020, police were called to reports of a collision involving one vehicle between junctions seven and eight, clockwise.
Officers attended and established that a silver Volkswagen Golf had collided with a safety barrier and two lamp posts.
Debris from the collision was subsequently struck by other vehicles.
The driver and passenger, a 26-year-old woman and 30-year-old man were taken to hospital with serious injuries.
No arrests have been made.
An investigation is underway.
PC Darren White, of GMP’s Serious Collision Investigation Unit, said: “This was a devastating collision which resulted in a young woman and man sustaining really serious injuries. Our thoughts are with them as they remain in hospital.
“Enquiries are ongoing to establish the full circumstances surrounding the incident and I appeal to anyone with information which may assist us or dash cam footage from the area at around the time of the collision to contact us.”
Anyone with information should contact the Serious Collision Investigation Unit on 0161 856 4741 quoting 199 of 11/06/20 or the independent charity – Crimestoppers, anonymously, on 0800 555 111.