A 14-year-old boy and a woman have died in a horror motorway crash.
The collision, which involved an HGV, a minibus and a number of other vehicles, happened between junctions 3 and 4 of the M58 motorway.
The 31-year-old driver of the HGV has been arrested on suspicion of causing death by dangerous driving, police said.
A number of other people also suffered serious injuries and are being treated at hospital.
The crash happened near Wigan at about 9am on Tuesday. A second crash followed on the same stretch of motorway shortly after and involved an HGV, a van and a car.
A woman and two men suffered serious injuries.
Images from the scene showed a lorry carrying scaffolding material and a number of bent and twisted cars.
Other images showed a white van had left the motorway and crashed into a nearby field.
Helen Green Purnell, a 48-year-old pharmacy assistant, saw the aftermath of the crash while out walking dogs.
She said: "All I can tell you is I saw the cars slowing down, and as I got there, there was a white van that had fallen down in to the ditch.
"It looked very serious. I've never seen anything like it in my life.
"The air ambulances were flying around. I've never witnessed anything like this before."
In a statement, Lancashire Police said: "We are working closely with partner agencies and the motorway remains closed in both directions for accident investigations. Diversions are in place.
"Our thoughts are with all of those affected by today's tragic incidents.
"Anyone who is concerned that someone they know may have been involved and who needs to speak to police should call 101 quoting log number 0523 of Tuesday, January 8.
"Anyone with information about either collision should call 101 quoting log number 275 of Tuesday, January 8."
