People on Sept. 25 started reporting stomach pains, vomiting, dizziness and high temperatures, Lysianskyi wrote on social media on Sept. 26.
The victims reported that the tap water in their houses had a chemical smell, he said. According to Lysianskyi, he received this information from doctors in Makiivka.
He said the water had become unfit for drinking after the local water disinfection system had broken down. The local water supply company, Voda Donbassa, had earlier warned residents to start boiling the tap water for at least 5-7 minutes, but not all of them followed these recommendations.
Lysianskyi posted a photo of white, cloudy water that had come from taps in Makiyivka – still discolored even after boiling.
The Russian-proxy authorities confirmed there had been a mass poisoning in the city.
Denis Pushylin, who now heads the Russian-occupation authorities in the so-called "Donetsk People's Republic," held an urgent meeting and confirmed that the mass poisoning was caused by a problem with water purification.
He added that the amount of chlorine used for water purification had been brought back to normal levels, and an investigation is being held into who is responsible for the incident, according to DAN, a news website controlled by the Russian-occupation authorities.
Makiivka, an industrial city located next to the region's capital city, Donetsk, has been one of the strongholds of the Russian-led forces in the Donbas since Russia launched its war on Ukraine in the spring of 2014.