Wildfires swept through dozens of villages in the Volgograd, Saratov and Samara regions, killing at least eight people and reducing more than 500 homes to smoldering ruins, officials said.
Friday's blazes in the provinces on the Volga River southeast of Moscow followed wildfires that killed at least 54 in central Russia in July and August during Russia's worst heat wave ever recorded.
Fires fanned by high winds and months of drought destroyed more than 500 buildings in at least 26 villages in the Volgograd and Saratov regions, injuring at least 17 people, Emergency Situations Ministry spokeswoman Yelena Chernova said.
Television pictures showed smoke rising from the blackened ruins of a village of wooden houses in the Volgograd region.
"Our house has burned down, everything has burned down. There's nothing left," said a middle-aged villager, her voice breaking as she spoke.
In the Samara region, traffic on a main highway near the automobile manufacturing city of Tolyatti was diverted for hours because of fire.
More than 2,500 people and at least five planes were involved in fighting the fires, the Emergency Situations Ministry said in a statement. Television pictures showed uniformed men running with buckets of water and shoveling dirt onto fires.
The ministry said its tanker planes and helicopters had made about 60 sorties to drop water on the fires by midday.
Emergency Situations Minister Sergei Shoigu said in televised remarks that by Friday night the fires were "localized and extinguished."
The ministry statement said the new fires were fanned by high winds and some started when the winds caused power lines to cross, shooting off sparks.
In a televised meeting with Shoigu, Prime Minister Vladimir Putin promised 1 billion rubles ($33 million) to each of the stricken regions to house those who lost their homes.
Opposition politicians say a government-mandated restructuring gutted Russia's forest management system during Putin's 2000-2008 presidency, badly slowing the response to the fires earlier this summer.
Opinion polls, however, indicate that Putin's popularity has not declined since the heat wave hit Russia in mid-July. A thick pall of smoke from the forest and peat-bog fires covered Moscow for several days.