Russian authorities said Saturday that 26 people died this week after consuming a hazardous home-brewed spirit in the Orenburg region bordering Kazakhstan.
The regional ministry told the state-owned news agency RIA that the death toll was up from the nine deaths reported on Thursday.
Another 28 people are suffering from symptoms of alcohol poisoning and some are reportedly in a coma.
Authorities work to control the situation
Denis Pasler, Orenburg governor, announced large-scale controls on sales and the withdrawal of purer forms of alcohol from the shelves while authorities work to track down those responsible for this case of mass alcohol poisoning.
"Alcohol consumption can be life-threatening," Pasler said.
There have been six arrests so far for allegedly producing and distributing alcohol unfit for human consumption.
Those arrested are believed to have sold the hazardous libation in the city of Orsk in the Orenburg region and other locations.
Deaths from homemade spirits not uncommon in Russia
This latest case of mass alcohol poisoning some 1,500 kilometers (900 miles) southeast of Moscow is one of the largest reported in recent years.
Such cases are not uncommon in Russia, especially in the countryside. Despite regulations on the sale of alcohol, many turn to cheap homemade alternatives.
In 2016, 76 died in Irkutsk after consuming a spirit that had been spiked with a window cleaner.
After that case, the federal government put in place tighter controls on the production and sale of alcohol, medicines, perfumes and other liquids that contain a high percentage of ethanol.