The Soviet authorities initially downplayed the severity of the disaster, but as the extent of the damage became clear, a team of scientists and engineers was dispatched to the site to assess the situation. They found that the reactor was still releasing radioactive material, and a concrete sarcophagus was built to encase the damaged reactor and prevent further radioactive material from escaping.

The disaster also highlighted the need for greater transparency and accountability in the nuclear industry. The Soviet authorities’ initial response to the disaster was criticized for being slow and inadequate, and it was clear that there were serious flaws in the safety culture of the nuclear industry.

At 1:23 a.m. on April 26, the power output began to decrease, and the operators made a series of critical errors, including turning off important safety systems. The reactor power began to increase, and at 1:24 a.m., the emergency shutdown button was pressed. However, it was too late, and a massive power surge caused a steam explosion, which destroyed the reactor building and released massive amounts of radioactive material into the environment.