Explainer-Why Russia and Ukraine are fighting for Chernobyl disaster site

An armoured personnel carrier is seen during tactical exercises, which are conducted by the Ukrainian National Guard, Armed Forces, special operations units and simulate a crisis situation in an urban settlement, in the abandoned city of Pripyat near the Chernobyl Nuclear Power Plant, Ukraine February 4, 2022. REUTERS/Gleb Garanich

WASHINGTON (Reuters) - Russian and Ukrainian forces fought on Thursday for control of Chernobyl, the still radioactive site of the world's worst nuclear accident and a factor in the collapse of the Soviet Union.

"Our defenders are giving their lives so that the tragedy of 1986 will not be repeated," Ukrainian President Volodymyr Zelenskiy tweeted before the defunct nuclear power plant, scene of a deadly fire and explosion in 1986, was captured by Russian forces.