Chernobyl disaster other undamaged reactors at the power station, with No. 3 continuing to produce electricity up into 2000. The accident motivated safety upgrades on all remaining Soviet-designed reactors in the RBMK (Chernobyl No. 4) family, of which eleven continued to power electric grids . The disaster began during a systems test on 26 April 1986 at reactor 4 of the Chernobyl plant near Pripyat and in proximity to the administrative border with Belarus and the Dnieper River. There was a sudden and unexpected power surge. When operators attempted an emergency shutdown, a much larger spike in power output occurred. This second
Chernobyl disaster the accident has meant that many cases that would previously have gone unnoticed (especially of cancer) are now being registered. The World Health Organization states, "children conceived before or after their father's exposure showed no statistically significant differences in mutation frequencies". This statistically insignificant increase was also seen by independent researchers analyzing the children of the Chernobyl liquidators. On farms in Narodychi Raion of Ukraine it is claimed that in the first four years of the disaster nearly 350 animals were born with gross deformities such as missing or extra limbs, missing eyes, heads or ribs, or deformed skulls; in