Twenty five people including four foreigners have died from drinking methanol-laced palm wine on the Indonesian resort island of Bali, police say.
American Rose Johnson, 48, Briton Alan Cole, 57, and Irish and Dutch citizens whose families requested anonymity, were among the people who have died over the past two weeks, hospital staff said.
The owner of a small rice wine factory has been arrested for allegedly making the lethal concoction with methanol — a toxic chemical compound often used as an antifreeze or solvent — instead of ethanol found in alcoholic drinks, police said.
"He is suspected of producing and selling alcohol containing methanol ... which can cause death," police spokesman Gede Sugianyar said.
"We are investigating whether he did it on purpose."
Two of his employees have also been arrested.
Mr Cole's Indonesian wife found her husband at home unconscious after he returned from a local drinking stall, the Daily Mail reported.
His vision was blurry and he had a seizure on the way to hospital, before suffering what was said to be a very painful and drawn-out death.
All the poisonings are believed to have come from the same batch, police said.
Drinking home brews has become increasingly popular in Indonesia after high taxes on alcohol pushed up the prices of beer, wine and spirits.
Indonesian authorities said they had already begun a crackdown on home brews following the poisonings.