• Updated

FILE – Tatyana Ignatenko, the mother of firefighter Vasily Ignatenko, grieves near his grave at Mitinskoye Cemetery in Moscow, Russia, on Wednesday, April 26, 2006, the 20th anniversary of the explosion and fire at the Chernobyl nuclear power plant in Ukraine. Vasily Ignatenko's crew was the first to respond to the disaster. (AP Photo/Alexander Zemlianichenko, File)

  • Updated

FILE - Lyudmilla Ignatenko, right, the widow of firefighter Vasily Ignatenko, mourns at his grave at Mitinskoye Cemetery in Moscow, Russia, on Thursday, April 26, 2001, the 15th anniversary of the explosion and fire at the Chernobyl nuclear power plant in Ukraine. With her at the cemetery is her son, who was not identified. (AP Photo/Alexander Zemlianichenko, File)

  • Updated

FILE - Relatives of firefighter Vladimir Pravik mourn at his grave at the Mitinskoye Cemetery in Moscow, Russia, on April 26, 2005. Pravik was among the first responders to the explosion and fire at the Chernobyl nuclear plant on April 26, 1986. (AP Photo/ Misha Japaridze, File)

  • Updated

FILE - Firefighters visit Mitinskoye Cemetery in Moscow, Russia, on Thursday, April 26, 2012, to honor those who died responding to the explosion and fire at the Chernobyl nuclear power plant on April 26, 1986. (AP Photo/Ivan Sekretarev, File)

  • Updated

FILE - Smoke rises from the cooling towers of the nuclear power plant Temelin near the town of Tyn nad Vltavou, Czech Republic, June 25, 2015. (AP Photo/Petr David Josek, File)

  • Updated

FILE - The Chernobyl nuclear plant is seen in an aerial view, showing the damage from an explosion and fire on April 26, 1986, that sent a radioactive plume over Europe. (AP Photo/ Volodymyr Repik, File)

  • Updated

FILE - A view of the closed nuclear plant of Biblis, Germany, south of Frankfurt, on March 16, 2021. (AP Photo/Michael Probst, File)