The people of Pripyat knew something had happened at the nearby power plant - but they only realised how serious it was two days later, when they were ordered to evacuate the city.
Drawing on accounts from eyewitnesses and survivors, as well as contemporary news reports and expert assessments, I'll tell the full story of the horrifying Chernobyl disaster.
This is the second of two episodes on this topic.
Visit www.greatdisasters.co.uk for the full transcript and more.
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