Russia’s emergency services have begun extinguishing round-the-clock wildfires raging near Moscow that have seen the city shrouded in thick, toxic smog for a second day.

“From today work on putting out peat bog fires will be carried out during the night as well,” the deputy emergency minister said.

“Up until now they had only been contained at night,” Alexander Chupriyan added.

The smog has seen levels of carbon monoxide reached some 6 times the safe level. The fires have been caused by a heat wave that has seen temperatures nudge 40 degrees Celsius (104 degrees Fahrenheit).

The smog is not expected to clear until at least Tuesday, when wind directions should change.

Much of the central part of European Russia has also been hit by wildfires, with blazes reported in over 20 regions. More than 50 people have died in the fires.

MOSCOW, August 7 (RIA Novosti)