As record hot temperatures reaching 35 degrees Celsius continue to bake Russia, wildfires threaten the nation's nuclear-weapons laboratory and other military facilities. A thick haze of wood smoke blankets Moscow.
While 3,000 firefighters battle flames and try to protect Russia's main nuclear weapons laboratory, the head of Russia's nuclear agency sought to reassure the public that all radioactive materials have been removed.
Nuclear chief Sergei Kiriyenko told President Dimitri Medvedev all explosive and radioactive materials have been taken away. He said he guarantees there is no danger to nuclear security, no threat of radiation, explosions, or environmental consequence.
Eight firefighting planes and 20 trucks are helping to keep flames out of Sarov, the location of the country's top-secret nuclear research facility and a city closed to foreigners.
With 400 new fires breaking out daily and wood smoke blanketing Moscow in a gray, acrid haze, President Medvedev cut short a working holiday in southern Russia and flew back to the nation's capital.
He found a city in which eye-watering smoke has infiltrated high-rise office towers and penetrated underground subway trains. With visibility sometimes reduced to 30 meters, drivers switched on their headlights at midday.
A spokeswoman for Moscow's state agency for monitoring air pollution, Yevgenia Semutnikova, said air pollution is three to four times higher than normal. She said even healthy people should minimize their exposure to pollution and should avoid being outdoors during peak pollution hours.
Russia's chief doctor, Gennady Onishchenko, recommended people wear air filter masks in the city and only exert a "minimum of physical activity."
Health experts say pollution levels in Moscow have climbed so high that living in the city is as damaging as smoking several packs of cigarettes a day.
Since last week, wildfires have killed 48 people and destroyed 2,000 homes. Responding to the emergency, Italy, Ukraine and Azerbaijan, have sent firefighting aircraft to Russia.
Meanwhile, President Medvedev publicly reprimanded the Navy Commander in Chief and fired the head of Naval Aviation and six other high-ranking officers for their part in trying for five days to cover up a disastrous fire at a storage depot near Moscow.