MOSCOW — Raging forest fires encircled a Russian city and tore through provincial villages Thursday, forcing mass evacuations as Moscow suffered through a record, weeks-long heat wave and smog cloud caused by peat-bog fires.

Some 212,506 acres were burning nationwide, and flames all but encircled the city of Voronezh, 300 miles southeast of Moscow. Forest fires on Moscow’s outskirts reached the city’s western fringe but were extinguished toward nightfall.

State television pictures showed the evacuation by ambulance of a Voronezh city hospital. TV said more than 800 patients were transferred to other facilities as flames approached the city’s outskirts and thick smoke lowered visibility. Hundreds of children were evacuated from at least seven summer camps, according to the regional Emergencies Ministry website.

Hundreds of homes in surrounding villages burned to the ground, the ministry said. The Interfax news agency reported that 340 homes were destroyed in a village near Nizhny Novgorod, around 250 miles east of Moscow.

Moscow on Thursday broke its all-time temperature record for the second time in a week. The mercury hit 100, beating by a fraction a record set Monday, the country’s news agencies reported.