It is "highly unlikely" that three people still missing in the rubble of the Didcot Power Station collapse are still alive, officials have said.
The search has been hampered by the "unstable" section still standing, they added.
The station closed in 2013 and was in the process of being demolished when it collapsed yesterday, killing one and injuring five.
There is a "huge risk" that the remaining section of Didcot Power Station could collapse, with emergency crews prepared for it to happen "at any minute", officials have said.
Oxfordshire Fire Service chief fire officer Dave Etheridge said the main priority was to reunite families with their missing loved ones, warning it was "highly unlikely" the three workers still unaccounted for had survived.
He said they were working closely with building and structural engineers and construction experts to help keep search and rescue officers safe as they continue to work through the rubble.
One person - a member of the demolition team - has already been confirmed dead, while five others remain in hospital in what police say is a "serious but not critical" condition.
Frustrated families of those missing since the power station collapse two weeks ago say they are heartbroken that rescue work has halted.
A biker group in the North East has paid tribute to 'Whitby' Mick Collings, who is thought to have died in the power station collapse.
One person has died and three others are still missing after a building collapsed at Didcot Power Station yesterday.