Information sought about white Mercedes box van in M5 crash
Police investigating a crash on the M5 in which four people died are seeking more information about a white van that was involved in the collision.
The crash happened between junctions 15 and 14 in South Gloucestershire on Saturday when the van crossed the central reservation barriers.
So far more than 50 witnesses have come forward with information.
Avon and Somerset Police added that formal identification of the victims would not be completed this week.
Insp Frazer Davey said: "Since Saturday, we've had more than 50 witnesses come forward with information so it'll take time to speak to all these people and take statements.
"The examination of the vehicles also continues and we're working closely with experts who will assist us in determining what caused this tragic collision.
"We're keen to hear from any witnesses who have not already provided their details, in particular anyone who may have been travelling on the southbound carriageway who saw the white Mercedes box van immediately prior to the collision."
One of the victims was named on Wednesday as Adrian Beaumont, 46, from Bristol.
He was driving a Seat Leon, along with his 42-year-old partner and two children, aged 12 and 10.
Three people remain in hospital following the crash.