Hospitals in the southern port city of Karachi have been inundated with nearly four dozen victims who drank the bootleg booze, senior police official Javed Bokhari said.
"The number of confirmed deaths is 27 but it could rise because some victims are still in a serious condition," Bokhari told AFP, raising the toll from 14 overnight.
The victims were labourers who lost consciousness after buying the alcohol on Thursday. Television footage showed some lying in hospital beds as relatives fanned them.
Bokhari said the police had arrested two men for illegally brewing alcohol and another two for selling the drink.
"We have also suspended the services of three senior police officials because they failed to check the crime happening in their area," he said.
Prohibition has been enforced in the Islamic republic since 1977, but clandestine production of alcohol is rampant, especially in rural areas.
Twenty-three people died from poisoned alcohol in October last year in the central city of Multan.
Officially two breweries operate in the country to provide alcohol to non-Muslim communities, who form three percent of the 160-million-member Muslim state.