The resulting release of radioactive particles led to the contamination of vast swathes of territory in modern-day Ukraine and Belarus, and prompted the Soviet authorities to create what is known as the Chernobyl Exclusion Zone around the crippled nuclear power plant.
Thousands of Soviet military and civilian personnel, who were later dubbed the Chernobyl liquidators, were involved in the effort to deal with the aftermath of the disaster, and thousands of civilians had to be evacuated from the affected area.