Over 140 fires have broken out in Kyiv and Kyiv Oblast over the last 12 days, greatly polluting the air in Ukraine’s capital, officials have reported.

The biggest fires are burning in the Chornobyl exclusion zone, where the firefighters are trying to put out 100 hectares of fire — about 180 soccer fields, according to Yegor Firsov, acting head of the State Environmental Inspection. Two firefighting planes and a helicopter have been dispatched to help extinguish the blaze there.