Up to 25 cars have been involved in a pile-up on a frozen motorway, Greater Manchester Police said today.
Drivers are being told to avoid the A627(M) in Oldham following the multiple crashes just before 8am.
A police spokesman said: "It is thought at least 25 vehicles are involved, with many more caught up in the traffic congestion.
"No exact details about casualties are known yet, but a number of motorists have sustained injuries.
"It is believed the cars may have skidded on a patch of black ice.
"A number of adjoining roads are also in the process of being closed so motorists are advised to find alternative routes as the motorway is expected to be closed for some time."