At the Russian measuring station Argayash, the highest level measured was 986 times that of the previous month, the Russian weather service said in a statement. At the Novogorny station, the measured levels were 440 times higher.
In mid-October Russian nuclear agency Rosatom denied that any of its facilities experienced any incidents — today, it again denied this.
Officials at Mayak have said the dose of radiation is 20,000 times smaller than the "allowed annual dose," and therefore "poses no danger to human health and lives."
In a statement released on Tuesday, environmental group Greenpeace demanded an in-depth inquiry "into potential concealment of a nuclear incident" and an investigation into public health risks.
Mayak was the location of the Kyshtym disaster in 1957, which remains the third-most serious nuclear accident ever recorded.
sad/im (AFP, AP, Reuters)
A lonely return
Gerd Ludwig took this picture of 92-year-old Kharytina in 2011. She chose to return to her birthplace Teremtzi, which is located inside the so-called exclusion zone near the Ukrainian disaster site. Kharytina lives in isolation in her wooden house, is almost deaf and has difficulty walking. Among the first journalists to access the site, Ludwig has been photographing Chernobyl for 30 years.
A late radiation victim
Veronika is five years old and suffers from leukemia. Hre mother Yelena was born in a town neighboring Chernobyl - four years before the nuclear disaster. Veronika's disease is a late consequence of the radiation that ensued after the meltdown. Gerd Ludwig took this picture at the Center for Radiation Medicine in Lyiv in 2011.
Timeless reminders of nuclear disaster
This picture was taken 25 years after the nuclear meltdown in Chernobyl. The image of a library in the town of Pripyat depicts the extent of the devastation since the disaster. Gerd Ludwig's images have become timeless witnesses to one of the greatest calamities of the industrial age.
A silent observer
According to the World Health Organization, about 4,000 people died in the immediate aftermath of the accident at Chernobyl. Another 4,000 perished on account of long-term complications after being exposed to radiation. German photographer Gerd Ludwig has repeatedly accompanied doctors, who continue to monitor nearby residents for radiation damage.
Poetic, but deadly
Some of Gerd Ludwig's images almost appear romantic in nature, with tender snow flakes falling onto a lush winter landscape in the twilight hour. But there's a yellow sign, sending off a crucial warning: Beware of the deadly radiation