A pedestrian was killed after being hit by several vehicles on the M66 near Bury.
It is believed the man was struck by a car on the northbound carriageway at about 8.15pm last night.
But the impact forced the man into the southbound carriageway where he was involved in collisions with other vehicles.
The man was pronounced dead at the scene.
No arrests have been made.
The southbound carriageway was closed for a number of hours but has now been reopened.
Police are appealing for information and dash cam footage.
Constable Nicholas Corlett, of GMP’s Serious Collision Investigation Unit, said: “This is a devastating incident for all involved and our thoughts are with them as our investigation continues.
“Our enquiries are in their early stages but we believe several people witnessed this collision and might have dash cam footage or information that could assist us.
“If this is you or you were on either side of the carriageway at around 8.15, please contact us as soon as possible.”
Anyone with information should contact the Serious Collision Investigation Unit on 0161 856 4741 quoting number 2726 of 20/12/19.
Alternatively, the independent charity – Crimestoppers, anonymously, on 0800 555 111.