Emergency services have declared the situation as a “large-scale incident”, with six ambulances on the scene as well as an air ambulance.
A tweet from the official NWAS account said: “Six patients are being treated for serious injuries after a collision with a vehicle”.
A spokesman for the ambulance service had previously described four of those injured as “walking wounded”.
Greater Manchester Police has confirmed the incident is not terror-related, the Manchester Evening News has reported.
A large area behind the Asda store has been cordoned off by officers.
Motorists have been warned of delays in the areas due to the incident.
Transport for Greater Manchester tweeted: “Due to a police incident at the junction of Rochdale Road and Moston Lane, long delays in the Harpurhey area.”
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