The families of three people still missing after part of a power station collapsed have visited the disaster scene as emergency crews admitted it was "highly unlikely" they are still alive.
A man named locally as Mick Collings died when a concrete and steel building at the derelict Didcot A site in south Oxfordshire came down on Tuesday afternoon while it was being prepared for demolition.
Five other people were taken to hospital, with all but one expected to be discharged by the end of the day.
Thames Valley Police said relatives of those missing had visited the power station site and discussed the search operation with the fire service. The military has also been brought in to aid the search.
Dave Etheridge, Oxfordshire Fire and Rescue Service chief fire officer, said the families of the missing were "obviously distraught".
He said: "We have explained to them we have not picked up any signs of life, but we are doing everything we can to locate their loved ones.
"It is highly unlikely they are alive."
He said the operation "may take several days, possibly several weeks".
"We remain committed and determined to return the missing people to their families, and work continues overnight," he added.
Police have yet to identify the deceased, although members of the Teesriders Motorcycle Club identified him as Mr Collings - also known as Whitby Mick.
There was no answer at Mr Collings's home in Brotton. It is understood family members have travelled down to Oxfordshire to identify his body.
Friends described him as "a big lad with a massive heart" and an "inspiration".
The red-brick semi-detached home, with a tidy front garden, is adjoined by a wooden garage with a sign saying "Mick's Man Cave" above the door.
A tribute on the Teesriders Motorcycle club's Facebook page read: "Words can not describe how gutted I am to be writing this.
"The accident that happened at Didcot power station yesterday has killed a good friend and dedicated member of Teesriders Mcc. All our thoughts go out to Lynn and all the family at this very sad time RIP Mick."
The building was due to be demolished when it collapsed and the Health and Safety Executive (HSE) has been investigating on-site.
It has emerged that the firm behind the demolition, Coleman and Company, had never done a job involving a power station.
In a corporate video posted on YouTube, project director Kieran Conaty said: "The client was made aware that this was our first power station - we'd never done anything like this.
"But we're that type of a company that we learn to adapt."
The rescue operation has involved the use of sniffer dogs, listening devices and drones and emergency services were considering deploying remote control probes to access the dangerous parts of the site.
Didcot A opened in 1970 as a coal-fired power station and was later converted so it could also generate power from natural gas.
It ceased generation in March 2013 and hundreds gathered to watch when three of its enormous cooling towers were blown up in July 2014 after dominating the town's skyline for more than four decades.
The incident comes 16 months after a major fire struck a cooling tower at Didcot B in October 2014.