Health officials in Russia say smog from wildfires has pushed pollution levels in the capital Moscow to six times higher than the maximum level considered acceptable for public health.
Forecasters say little relief appears imminent, with the country's worst heat wave in decades expected to continue for at least the next few days.
A thick haze continues to hang over Moscow, with smoke from forest and peat bog fires infiltrating homes and offices and forcing people to wear protective masks.
Reports say flights through Moscow's airports are also still facing disruptions, with some flights canceled or diverted due to limited visibility.
The Emergencies Ministry has reported nearly 600 separate fires burning nationwide, mainly across western Russia.
compiled from agency reports