The Ukrainian military on Saturday reported renewed shelling at the Zaporizhzhia Nuclear Power Plant complex in southern Ukraine, hours after the European Union late Friday joined the United States in calling for a demilitarized zone to be created around the plant immediately.
International concern has grown as shelling at the plant raises the risk of igniting a fire or causing other damage that could spiral out of control and lead to a nuclear accident.
Ukraine has accused Russia of directing strikes there to cut off energy supplies to other cities and to try to discredit the Ukrainian military in the world’s eyes. The Russians say Ukraine is doing the shelling.
In his nightly address on Saturday, President Volodymyr Zelensky of Ukraine said the situation at the nuclear power plant was a threat to the rest of Europe, too. Every day that Russians forces occupy the plant and the region around it “increases the radiation threat to Europe so much that, even in the peak moments of the confrontation during the Cold War, this did not happen.”
On Saturday, the Ukrainian military intelligence agency accused Russia of using the occupied town of Vodyane, which is near the plant, as a staging ground to shell the facility. They also accused Russia of planning a false-flag propaganda event to make it appear that the Ukrainians are responsible for the hostilities around the complex.
The intelligence agency said that, among other things, Russian forces were flying Ukrainian flags in positions where their artillery was located.
The claims could not be independently verified, but they reflect the Ukrainian belief that Russia is using the plant as a form of nuclear blackmail aimed at scaring the Ukrainians and their international allies about the consequences of any effort to reclaim land now occupied by Russia.
At the same time, the Russian state media outlet Ria Novosti reported that Ukraine had launched an artillery attack on the plant, firing at least nine shells that landed near the complex. The report quoted a local official in Russia’s occupation administration. It could not be independently confirmed.
It was not immediately clear what damage was caused by the renewed shelling on Saturday.
Both sides would suffer if a meltdown occurred at the plant, Europe’s largest, and spread radioactive material.
While such plants are designed to withstand a range of risk — from a plane crashing into the facility to natural disasters — no operating nuclear power plant has ever been in the middle of active fighting, and this one was not designed with the threat of cruise missiles in mind.
The concrete shell of the site’s six reactors offer strong protection, as was the case when the No. 1 reactor was struck in March, officials say. More worrying is the chance that a power transformer is hit by shelling, raising the risk of a fire.
If a fire were to break out at the power transformers and the electric network were taken offline, that could cause a breakdown of the plant’s cooling system and lead to a catastrophic meltdown, said Edwin Lyman, a nuclear power expert at the Union of Concerned Scientists, a private group in Cambridge, Mass.
He noted that the loss of coolant during the Fukushima accident in Japan in 2011 had resulted in three reactors undergoing some degree of core meltdown.
If the cooling is interrupted, Dr. Lyman said, the nuclear fuel could become hot enough to melt in a matter of hours. Eventually, it could melt through the steel reactor vessel and even the outer containment structure, releasing radioactive material.