Fifteen people have died and another 400 have been taken to hospital in Pskov in Russia after apparently drinking tainted alcohol.
Russia's thirst for vodka attracts unscrupulous suppliers
Authorities have declared a local emergency, allowing them to seize and test bottles of alcohol on sale.
Dozens of people have died elsewhere in Russia from similar causes recently.
Russian Interior Minister Rashid Nurgaliyev has said poisoning by counterfeit alcohol kills 42,000 Russians every year.
Fake vodka and other unregulated liquors are thought to be the main culprits.
"More than 400 people in the region of Pskov were hospitalised over the last three weeks with a form of toxic, non-contagious hepatitis," said a senior official in the health department in Pskov, which is near the border with Latvia.
In other cases of alcohol poisoning, 18 people died over several days in the Irkutsk region of Siberia, Itar-Tass news agency reported.
And Interfax news agency said that in the Ural mountains town of Kirov, 21 people had died.