A man has died after being hit by four cars as he walked on the M66 motorway near Bury.
He is believed to have been walking along the carriageway at about 02:00 BST when he was hit by a car travelling northbound.
He was then struck by three other cars travelling southbound, police said.
The motorway remains closed southbound between Ramsbottom and Bury junctions and diversions have been put in place.
Emergency services have been at the scene overnight and investigation work is being carried out.
Police said the victim had been identified and his family had been informed.
A 19-year-old man has been arrested on suspicion of driving under the influence and remains in police custody.
Officers are appealing for witnesses and anyone with dash cam footage to contact them. (BBC)