The driver of a lorry involved in a crash on the M6 which left five people dead has been arrested on suspicion of causing death by dangerous driving.
A 60-year-old man from the West Midlands is being questioned by officers, Staffordshire Police said.
The deadly crash involving a Nissan Micra happened on a southbound stretch of the motorway between Stoke-on-Trent and Stafford at about 4.30am on Wednesday.
Police said four women and a man travelling in the car were killed, while another man was taken to hospital with serious multiple injuries.
He remains in a serious but stable condition.
Police are still working to formally identify the victims and trace next of kin.
The motorway has been closed southbound between junction 15 and junction 14 all morning, but is now expected to reopen at lunchtime.
Earlier, delays had stretched back to junction 16 and motorists were urged to follow diversions and find an alternative route.
Trapped traffic which had been backed up behind the scene of the collision since the early hours was released later in the morning after engineers removed the central barrier.
Dashcam footage from drivers heading northbound past the scene showed a screen had been put up around the site by the emergency services as traffic filtered by.
In a statement, Staffordshire Police said: "We can confirm that the lorry driver involved in this morning's collision has been arrested on suspicion of causing death by dangerous driving.
"The 60-year-old man, from the West Midlands, has been taken into custody for questioning."
The ambulance service said the car's driver and four passengers had been killed in the crash, after a "significant collision" involving an HGV.
One other occupant in the car, a man in his 40s, suffered multiple serious injured and has been taken to Royal Stoke University Hospital.
In a statement, West Midlands Ambulance Service said: "When emergency services arrived, they discovered a car with six occupants inside which had been involved in a significant collision with a HGV.
"Sadly, it quickly became apparent that nothing could be done to save the driver and four passengers.
"All five were confirmed dead on scene."
The male driver of the lorry was uninjured.
A detailed investigation is continuing and the police have urged any witnesses who have not yet come forward to contact the force on 101.