A stretch of motorway closed after one of the worst multiple vehicle crashes in memory has reopened - as police focus their attention on a rugby club fireworks event held close to the scene.
The section of the M5 near Taunton in Somerset, which had been closed since Friday evening's tragedy, was reopened on Sunday night.
Investigators said the theory that smoke from the display had drifted across the road and caused the 34-vehicle pile-up, which claimed seven lives and left 51 injured, was now their "main line of inquiry".
Tributes have continued to be paid to the victims of the incident.
The revelation came as elderly couple Tony and Pamela Adams, from Newport, south Wales, were named locally as being among the victims of Friday's pile-up.
The Reverend Andrew Willie told the congregation at St Mark's Church, where the couple attended, that they had died.
He said Mr Adams, who was a church reader and former warden, and his wife, who was involved in parish activities, "will be sorely missed".
Neighbour and close friend Doreen Martin, 88, said the pair were in their seventies and had a large family of children and grandchildren.
"It's such a shock. They were a lovely couple," she said.
Avon and Somerset Police are yet to confirm the identities of any of the seven victims, but revealed they are now conducting both criminal and road policing investigations.
Meanwhile, it was reported that the crash has left a young woman in a coma and her wheelchair-bound father and sister dead.
Emma Barton, believed to be 19, was said to have been travelling in a car with her boyfriend Christopher Burbull, father Michael and sister Maggie, when they were caught up in the chaos .
It is believed the group had been to a funeral and were returning to the family home in Windsor, Berkshire.
Mr Burbull, of Slough, Berks, was also admitted to hospital following the crash, it was said.
Another possible casualty was named as Malcolm Beacham, from Woolavington in Somerset.
Online tributes last night appeared in memory of Mr Beacham, who is said to be the event co-ordinator of a re-enactment group.
One comment, left on the Living History website by a user named Martin, said: "For those that had the privilege of knowing him Malcolm was a fantastic guy, a true stalwart of the re-enactment community from The Company Of Chivalry, he was involved in the accident on the M5 on Friday, you will be sorely missed m8."
Lorry driver Terry Brice from Bristol was also named in reports as being among the victims.
A Twitter post, believed to be made by his teenage daughter Jessica, said: "rest in peace daddy, i love you so much, you will never be forgotten, not a day will go by where i won't hope you'll walk through that door."
Police inquiries into the firework theory started after witnesses reported "significant smoke" across the carriageway that was "impossible to drive through".
Taunton Rugby Club announced in a statement that it was "working closely with Avon and Somerset police to assist with their investigations".
Assistant Chief Constable Anthony Bangham said: "Our main line of inquiry has now moved towards the event that was on the side of the carriageway and we do believe that while there was fog and it was difficult conditions in the area, that actually from witness evidence there was very significant smoke across the carriageway.
"That in effect caused a bank similar to a fog bank, which was very distracting and very difficult to drive through.
"We will be doing everything we can to find out as quickly as we're able to what's behind that."
Witnesses at the Taunton Rugby Club fireworks display were being interviewed, he said, adding that accountability was "clearly something we will look at".
He went on: "We believe from the witnesses and from what we're being told that it was smoke and not fog.
"The vehicles and people who were entering into the smoke bank have just described it as being impossible to drive through and that of course causing them to brake."
The police investigation will look at how the fireworks event was organised, what permission was given for it and what was and was not meant to be happening there, Mr Bangham said.
Cordons are expected to remain around the rugby club and its pitches today as officers continue their inquiry.
Emergency workers described the crash as "the worst road traffic collision anyone can remember".
The motorway was closed in both directions between junctions 24 and 25 following the incident, which took place at about 8.25pm in wet and foggy conditions on the northbound carriageway.
The Highways Agency said the road was reopened at around 9pm last night after emergency workers completed the painstaking process of clearing the wreckage.
Of the casualties, 25 were taken to Yeovil District Hospital and 17 of the more seriously injured to Musgrove Park Hospital in Taunton. Nine others were taken to a temporary holding unit set up by the ambulance service.
Musgrove Park Hospital said four of those it had received had now been discharged.
Formal identification of the victims is expected to take place in the coming days, police said.