A man has been arrested after a woman and a 14-year-old boy died in a multi-vehicle motorway crash.
The crash between junctions three and four of the M58 near Wigan involved an HGV, a minibus and a number of other vehicles, at about 9am on Tuesday.
The driver of the HGV, a 31-year-old-man from Chorley, has been arrested on suspicion of causing death by dangerous driving, said Lancashire Police. A number of other people also suffered serious injuries and are being treated at hospital, added police.
A second crash happened shortly after the first incident 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.
A spokesman for Allied Scaffolding said: "We are fully aware of the situation and it is related to our company.
"We are in full co-operation with the police and authorities and will give them our full support.
"Our main concern at this stage is for those involved in the crash."
Helen Green Purnell, 48, a pharmacy assistant from Skelmersdale, 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 and 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."
Andy Bonner was at the scene: