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Fires covering more than 10,000 hectares across the Chernobyl exclusion zone could lead to spiked radiation pollution levels in the air spreading on prevailing winds heading west, Ukrainian officials have warned.
Russian military forces are to blame for 31 forest fires, said Lyudmila Denisova, the commissioner of a Ukrainian human rights group.
Deputy Prime Minister Iryna Vereshchuk said the fires threaten Ukraine and hundreds of millions of Europeans.
“Significant fires have started in the exclusion zone, which can have very serious consequences,” Ms Vereshchuk said on Telegram.
“However, today it is impossible to control and extinguish fires in full due to the capture of the exclusion zone by the Russian occupation forces.”
She said the Russian army was “militarising” the site and storing ammunition “in close proximity” to the station.
“It should be noted that recently Russian occupation troops have been using old and unconditional ammunition more often, which increases the risk of their detonation even when loading and transporting,” she said.
“In the context of nuclear safety, the irresponsible and unprofessional actions of Russian servicemen present a very serious threat not only to Ukraine but to hundreds of millions of Europeans”.
The International Atomic Energy Agency said on Sunday “the situation remained unchanged” in relation to safeguards at Chernobyl and other nuclear plants in Ukraine.
The UN nuclear watchdog last week said forest fires around Chernobyl did not pose a major radiological risk.
Since March 9 the International Atomic Energy Agency has not received live data from Chernobyl. It said on Sunday it was concerned about the lack of staff turnover at the plant since March 20.
The exclusion zone is an area of about 2,600 square kilometres around the nuclear plant.
Ms Denisova said dry and windy weather could make the fires harder to tackle.
“Control and suppression of fires is impossible due to the capture of the exclusion zone by Russian troops. As a result of combustion, radionuclides are released into the atmosphere, which are transported by wind over long distances.”
She warned there was a risk of “irreparable consequences not only for Ukraine but also for the whole world”.
“Catastrophic consequences can be prevented only by immediate de-occupation of the territory by Russian troops. Therefore, I call on international human rights organisations to take all possible measures to increase pressure on the Russian Federation to end military aggression against Ukraine and de-occupy high-risk areas,” Ms Denisova said.
Russian forces seized the plant on February 24, the first day of the invasion.
Chernobyl's number four reactor exploded on April 26, 1986, causing the world's worst nuclear accident. Hundreds were killed and radioactive contamination spread west across Europe.
The reactor number four building is now encased in a double sarcophagus to limit radioactive contamination.
The original sarcophagus, constructed by the Soviets, deteriorated over the years. A new one was built over it and completed in 2019.
The plant's other three reactors were gradually shut down after the disaster, the last in 2000.