Ryazan, a Russian region east of Moscow, announced a state of emergency on Monday after a series of wildfires devastated more than 8,000 hectares (20,000 acres) of land.
Acting Governor Pavel Malkov said on Telegram that the measure would facilitate the mobilization of resources “to protect the inhabitants and the territory”.
Malkov added that aerial surveillance indicated that 9,000 hectares of forest had been swallowed up.
Greenpeace cited satellite images in estimating that at least 11,000 hectares had been destroyed.
Local authorities reacted after their Moscow counterparts reacted to smoke from the fires reaching the capital.
Moscow Mayor Sergei Sobyanin, who visited the affected region on Monday, announced on Telegram that 8,500 people and 200 units of specialized equipment, including helicopters, would be dispatched to help put out the flames.
Regional authorities previously said 900 firefighters, seven planes and 10 helicopters were dealing with the blaze in what Sobyanin said was a hard-to-reach area.
Scientists blame a series of wildfires across Europe in what has been a summer of unusually high temperatures on climate change and Russia was no exception, suffering especially in Siberia and the Far East of the country.