A landfill in southern Russia's Krasnodar region caught fire on Tuesday, sending potentially hazardous smoke over surrounding residential areas, activists and media reported.In a video posted online by a local activist group,large clouds of brownish-gray smoke could be seen billowing over fields and houses near the landfill, which is located outside the village ofPoltavskaya."The poisoned smoke, containing the entire 'Periodic Table of Elements,' has enveloped the village, the video's description read.There's no air to breathe, we need to evacuate children and the elderly, protect our respiratory organs, and hope that the burning hectares of trash can be extinguished quickly," it continued.The blaze at the landfill, which is situated next to large rice fields, engulfed an area of five hectares,Russias Emergency Situations Ministry said.Krasnodar's regional Prosecutor's Officelaunched an investigation into the incident.While the cause of Tuesday's fire is still unknown, local activistNatalia Garyaeva toldthe independent Govorit NeMoskva news outlet that she suspected straw clearing that occurred the day before was to blame.Rospotrebnadzor, Russia's consumer protection watchdog, saidit did not detect unsafe levels of air pollutants in areas near the burning landfill.However, some local residents disagreed and took to social media to criticize the watchdog's assessment."[Krasnodar region Governor Veniamin Kondratyev] forces Rospotrebnadzor to give him his sought-after analysis!!!We're starting to suffocate, and the wind is turning toward the village," an activist group wrote on the messaging app Telegram.In August, a group of Russian soldiers fighting in Ukraine threatened to abandon their posts unless the Poltavskaya landfill was closed.The soldiers' warning was just the latest plea to authorities in adecade-long fightby residents of Poltavskaya to shutter the waste dump, which was built in 1992.