The M6 was closed in both directions on Wednesday night and a man has been arrested due to a “major incident”, the police said.
Hundreds of motorists are still trapped between junction 15 and 16 near Stoke-on-Trent, Staffordshire due to the closure. The southbound carriageway has now re-opened.
The major disruption was sparked by police stopping a vehicle, reportedly a lorry, which a number of people, thought to be migrants, then got out of.
A statement from Staffordshire Police said: “Officers from Staffordshire Police have stopped a vehicle on the M6 between Junctions 15 and 16 this evening (9 January) and a number of people have exited the back of the vehicle.
“A man has been arrested at the scene and is currently in police custody.”
A number of eyewitnesses have told Stoke on Trent Live that police have been pulling over and checking lorries.