A thick, milky haze shrouded the city, and many Muscovites peered with red-rimmed eyes over the tops of surgical masks or wet handkerchiefs.

Image Smog from wildfires outside of Moscow hung over the city on Friday. Credit... Natalia Kolesnikova/Agence France-Presse — Getty Images

By 1:40 p.m., the city’s environmental protection agency said the concentrations of carbon monoxide were five times as much as acceptable levels, while particulate pollution was three times as much.

The heavy smoke disrupted flights into Moscow. At Domodedovo Airport, visibility on the runways was down to about 400 yards on Friday, the news agency Itar-Tass reported. Dozens of arrivals were delayed or late, the airport reported on its Web site.

Artillery rockets housed at the Alabinsk base, about 45 miles southwest of Moscow, were moved to safer ground away from the fires, a Defense Ministry spokesman told reporters.

The fires posed a different threat when they burned through forests toward a nuclear missile warning center outside Moscow; the center’s fire brigades suppressed two fires Friday that had threatened the site, news agencies reported, citing a Russian Space Forces spokesman.