The Zaporizhzhia nuclear plant, Europe’s largest nuclear reactor and the ninth-largest in the world, was damaged by fire during a battle near the city of Enerhodar, raising concerns of a nuclear disaster similar in scale to the Chernobyl accident.

The Russian military began to shell the power plant Thursday, according to Energoatom, Ukraine’s state-run nuclear energy company. The agency’s director, Ihor Murashov, said in a Telegram post that “nuclear safety at [the plant] is violated.”

“We are doing everything possible, but the fire continues,” Murashov wrote, adding that firefighters had not been allowed near the fire because of the ongoing fighting around the power station. “There are huge risks,” the director wrote of the ongoing clashes. “Reactors are in danger.”

After a conversation with Ukrainian energy minister German Galushchenko, U.S. secretary of energy Jennifer Granholm stated that the Zaporizhzhia power station was “protected by robust containment structures.” She added that the nuclear reactors at the site were “being safely shut down” and radiation detectors in the facility had not detected elevated levels, suggesting that the plant’s fissile material containers had not been breached.

After speaking with Ukrainian president Volodymyr Zelensky regarding the disaster, President Joe Biden called on Russian leader Vladimir Putin to “cease [his] military activities in the area and allow firefighters and emergency responders to access the site,” according to a White House statement.

The statement also indicated that the president had received a briefing on the situation from the Department of Energy’s Under Secretary for Nuclear Security, Jill Hruby. “The President will continue to be briefed regularly,” the statement added.

Ukraine is home to Chernobyl, the Soviet-era nuclear power plant that suffered a catastrophic meltdown in 1986 near the Ukrainian city of Pripyat. Roughly thirty workers died immediately during the plant’s cleanup and sealing, and thousands were estimated to have had their lives shortened due to the disaster.

Fears of another disaster at the Chernobyl site were sparked last week when Russian forces captured the reactor area after a fierce battle, during which the plant’s containment shell was reportedly hit by artillery rounds.

The presence of four active nuclear power plants in Ukraine has led Galushchenko to request that NATO impose a no-fly zone over Ukraine, according to Ukrinform.

Trevor Filseth is a current and foreign affairs writer for the National Interest.

Image: Reuters.