Major incident at UK power station
A "major incident" has been declared and a fatality reported after a building collapse at Didcot Power Station.
Emergency services were called at 4pm to the site in south Oxfordshire amid reports of an explosion.
Rodney Rose, deputy leader of Oxfordshire County Council, told the Oxford Mail: "I have been told there has been one fatality, but the rest is currently unknown. The fire service is there now and we are still trying to find out if this was a demolition."
Mr Rose, who sits on a committee responsible for Thames Valley Fire Service, added: "At the moment this is being treated as a collapsed building, not an explosion, but there was a bang."
Six ambulances and two air ambulance have been sent to the scene, South Central Ambulance Service said.
A spokesman said: "We are describing it as a major incident," adding that he thought there would be casualties.
Photographs from the scene showed part of a building missing, which appears to be the former coal-fired Didcot A plant.
The plant closed in 2013 and h undreds gathered to watch when three of its enormous cooling towers were demolished.
More demolition work at the site was under way.
David Cooke, whose company Thames Cryogenics have a building overlooking the power station, said: "Our building shook and as we looked out of the window, the end of the main turbine hall collapsed in a huge pile of dust.
"It totally obscured the towers and must have drifted across the roads and main rail line. What's left looks a tangled mess.
"The dust was hanging over the area for five to 10 minutes.
"First thought was it didn't looked planned, followed by the thought that people are going to have been hurt."
Pictures from the scene showed a significant chunk of a building in the defunct Didcot A site has collapsed, with a large amount of debris on the ground.
There is also a heavy emergency services presence.
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 its cooling towers were blown up in July 2014 after dominating the town's skyline for more than four decades.
According to the RWE npower website the total demolition of the site is expected to be complete by the end of this year.
The incident comes 16 months since a major fire struck a cooling tower at Didcot B in October 2014.
The blaze affected 50% of the station output - supplying a million homes.l
Eyewitness Bill McKinnon, who lives in Didcot near the scene of the explosion, told the BBC: "I was sitting in my front room, I can see the power station quite clearly from where I am, it's only about 400 yards away.
"About 4 o'clock, when I heard the explosion and the very loud rumbling, by the time I had got up and looked out of the window there was a huge cloud of dust which came through and over our village.
"When that had cleared I noticed that half of the old power station, where they used to keep the generators, half of that was missing.
"There wasn't any physical feeling, it was only noise. When they took down the cooling towers a couple of years ago it was about the same volume as that. It was quite loud."
He added: "I was a little bit surprised because normally the contractors let us know when they are going to do explosions, so I was a bit surprised because we hadn't heard anything.
"Very shortly afterwards the air ambulance turned up and then fire engines and ambulances started arriving, and a little while after that another air ambulance turned up, and I think they are still there."
Mr McKinnon said the explosion took place in a large building which housed the generators for producing power.
Ed Vaizey, Conservative MP for Didcot and Wantage, said on Twitter: "Very concerned about terrible events at Didcot power station. Praying for workers and their families."
He told BBC News: "There is a coal power station there and there is a gas-fired power station there, and the coal power station has been decommissioned.
"There are six cooling towers, they are the symbol of Didcot, and three of those towers were brought down in a properly-controlled explosion a year ago and the next three are due to be brought down soon.
"Obviously there are large buildings also to be taken down by professional contractors. I don't know if this is related to that."
He said there would have been a number of people working at the site.
He added: "I am very concerned there may have been casualties."
Nicola Blackwood, MP for Oxford West and Abingdon, tweeted: "Thoughts with all affected by incident at Didcot Power Station. Strength & thanks to emergency responders."
Oxford University Hospitals NHS Foundation Trust said "casualties" were being taken to the John Radcliffe Hospital in Oxford and asked the public to stay away unless suffering "serious or life-threatening emergencies".
A spokesman said: "C asualties are being directed to the emergency department of the John Radcliffe Hospital which has been made ready to receive them.
"We are not able to release any information on numbers of casualties at this time.
"We are grateful to members of the public for avoiding attending our emergency department for anything other than serious or life-threatening emergencies."
A GMB union official t old the Press Association: "We understand that workers were preparing two boilers for demolition in the coming weeks. This led to the collapse of a building."
The official said he did not believe there had been an explosion.