A lorry driver has been airlifted to hospital and is in a critical condition after a serious crash between junctions 22 and 21 of the M62.
The M62 has been closed after a lorry crashed through the central reservation near Milnrow.
At around 8.15am, the lorry went through the reservation, onto the opposite side of the motorway, colliding with a number of vehicles, police have confirmed.
Witnesses have reported ambulances, fire engines and police cars at the scene.
It is not yet known when the motorway will open and traffic is building on surrounding roads, particularly Huddersfield Road, Rochdale Road, Oldham Road and Ripponden Road due to traffic being diverted from the area.
A statement from Highways England said: "The M62 remained closed between junction 22 (A672: Ripponden, Sowerby Bridge) and junction 21 (A640: Milnrow, Shaw) following a serious collision.
"A diversion is available for road users to follow around the closure.
"If travelling eastbound exit at J21 and follow the A6193 eastbound (towards Milnrow). At the the third roundabout turn right on to the A640 southbound through Newhay and on to Denshaw. In Denshaw turn left on to the A672 northbound and remain on this road to J22 of the M62.
"Westbound travellers should exit at J22 and follow the above route in reverse (A672 southbound to Denshaw, turn right on to the A640 northbound through Newhay and on to Milnrow and rejoin the M62 and J21).
"Please note this diversion route is comprised of rural, single carriageway roads and therefore is likely to be congested.
"As the M62 is expected to be closed for a protracted period road users intending to travel on this section of road are strongly urged to consider alternative routes and to allow additional time for their journey."
