Traffic on the M5 federal highway was halted some 30 km before the city zone.
Wildfires have been raging in forests on both sides of the M5 "Urals" federal highway linking Moscow and the Urals near the city of Togliatti in the Volga area, the regional emergencies service said on Friday.
"Due to strong winds there is a threat that the fire might spread to filling stations and wayside cafes," the source said.
The Samara Region, in which Togliatti is located, borders the wildfire-hit Saratov Region.
Togliatti city authorities have re-introduced the state of emergency, lifted on Wednesday.
Traffic on the M5 federal highway was halted some 30 km before the city zone.
A rescuer working at the scene said two firefighting helicopters are expected to arrive by 9:00 Moscow time [5:00 GMT].
RIA Novosti
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