Forty nine fires on more than 6,000 hectares were extinguished on Wednesday in Buryatia, the Altai, Trans-Baikal and Krasnoyarsk territories and the Irkutsk, Novosibirsk and Tomsk regions, where 1,860 firefighters, including smoke jumpers, and 30 aircraft fought the blaze.
The fires were caused mainly by carelessness of people and thunderstorms.
There have been 6,390 forest fires on 1,156,000 hectares in Siberia since the beginning of the warm season
The area of fires enlarged from 3,500 to 4,900 hectares in the Krasnoyarsk territory over the past 24 hours. Fifty six outbreaks, including three large, were reported in the region on Thursday.
There was no threat to residential areas, the regional forest fire fighting centre told ITAR-TASS.
The taiga was afire in 12 districts in the Krasnoyarsk Territory, including two fires on 131 hectares in restricted forest reserve areas.
Specialists said the main cause was a "dry" thunderstorm.
About 20 aircraft participated in operations to fight wildfires, transport people and monitor the situation.
A state of emergency has been in force in the Krasnoyarsk Territory since June 25.
This year, 1,312 fires have raged on more than 82,500 hectares in the region. Last year, 548 wildfires destroyed 22,500 hectares during the same period.