BBC: None of them had any idea what they were really going into. The group I spoke to said they worked on deactivating the third and fourth reactors. They then helped build the structure that has contained the worst of the radiation until now. By Christian Borys
'It took a nightmarish 206 days to build that first sarcophagus, using 400,000 cubic metres of concrete and 7,300 tonnes of metal framework. "We worked in three shifts, but only for five to seven minutes at a time because of the danger,” the group’s leader, Yaroslav Melnik, told me. “After finishing, we'd throw our clothes in the garbage.”
'In total, around a million men and women from across the Soviet Union were brought in to help with the initial clean-up and containment. Helicopters flew over the reactor dropping sand, lead and other substances to extinguish the fire and prevent radiation from escaping. Coal miners dug underneath the reactor’s core so that liquid nitrogen could be pumped in to cool the nuclear fuel.
'Others removed contaminated materials and evacuated civilians. Reports differ but some suggest that thousands of these liquidators died during their work. The consensus is that most of them suffered horrific long-term illnesses from acute radiation exposure.'