Minister of Internal Affairs of Ukraine Arsen Avakov reports that out of 15 outbreaks of fire in the ecosystems of the Zhytomyr region, rescuers have already eliminated six and localized five outbreaks.
“The reason for the air pollution around Kyiv is … fires in the Zhytomyr region. Some 7,800 hectares of forest litter burned out. There were 15 outbreaks, with six eliminated, five localized, we’re working under another four outbreaks. Three airplanes, a fire train, 100 units of special equipment and more than 600 people were engaged for extinguishing. We’ll get through this!” Avakov wrote on his Twitter account on Saturday afternoon.
(c) Interfax Ukraine

Finally they got around to publishing the real reason for the pollution in Kyiv. It had nothing to do with Chornobyl, but including the word Chornobyl in an article will get attention. I know for a fact that the wind for the last two weeks has been coming from a Westerly direction, and not from the North, where Chornobyl is located. I noticed this smell of burning 3 days ago, and thought it was some local guy burning rubbish, it was later I found out the reason for the smell was coming from these fires in the Zhytomyr region, which is to the West Kyiv.
I mentioned this yesterday and I provided a link to a Ukrainian site that includes a satellite image. In it you can clearly see from where the smoke originates.
Yeah, seems nobody did anything about this fire until it started burning a village down.