Yuvchenko then went outside to get a clearer picture of what was happening. There, he saw "a huge beam of projected light flooding up into infinity."
"It was light-bluish," he said, "and it was very beautiful."
Back inside, he propped open a door for three workers who had been ordered to lower the control rods in the reactor hall.
"All three of them died very soon afterwards," Yuvchenko told New Scientist. "That wall and the door basically saved my life."