A cloud of harmful smog has enveloped Moscow, raising airborne pollutants to four times the norm and prompting doctors to urge residents to stay indoors as the city swelters in a record heat wave.
Officials have said the smog, which has plunged the Kremlin and other famous landmarks into a dull haze for days, is the capital's worst since 2002.
The cloud has drifted in from dozens of peat bog and forest fires in rural land south and east of the city, Emergencies Ministry officials have said.
Health officials have urged locals who have to venture outside to don face masks to ward off the worst of the poisonous carbon monoxide, nitrogen dioxide and carbolic acid particles in the smog. And all the while, the city has been sizzling in record temperatures. While Moscow routinely has hot summers, this year has been a record-breaker, with daily maximums around 95 (35 degrees Celsius) for two weeks. The all-time high of 99.5 (37.5 degrees Celsius), was set on Monday.
Some Soviet-era housing in Moscow has such poor insulation that apartments offer little reprieve. The majority of Russian offices - especially businesses that cannot afford a spot in steel-and-glass office buildings - have no air-conditioning. On Moscow's subway system, which serves at least eight million people a day, temperatures at some stations have sparked angry exchanges between consumer watchdogs and transport officials over the lack of adequate air conditioning.
With the smog and heat, mortality rates among risk groups are sure to spiral, said Vladimir Kuznetsov, acting head of the Independent Centre for Environmental Policy. "There will be sad news for some people with severe allergies, heart conditions, asthma, other breathing conditions and the like," he said.
With officials advising people to stay indoors, a way to fight off the worst effects of the heat and smog for people with no air conditioning is to hang wet blankets, physicians said, which attract dust particles and cool the air. Residents are also urged to change clothes regularly, take showers, and clean noses and throats regularly to rinse away harmful smog particles.
While the heat, which is relatively mild for the United States but highly unusual in Northern Europe, is expected to ease in the coming days, the smog could be around for weeks, Mr Kuznetsov said.
Peat bog fires are notoriously difficult to extinguish. When moisture is low, such as during heat waves, the peat, which is high in carbon, can ignite and smoulder underground. The Moscow region, an official entity surrounding but not including the city, is home to thousands of hectares of peat bogs. Many are concentrated in the Shatura region, where smouldering frequently goes undetected.
Environmentalists said the 2002 smog that blanketed Moscow killed hundreds of people.