More than 2,000 WineLab liquor stores across Russia have remained shut for three days following a ransomware attack on their parent company, one of Russia’s largest alcohol producers. Signs on WineLab doors said the stores were closed due to “technical issues.”

The attack crippled parts of the Novabev Group’s infrastructure, affecting WineLab’s point-of-sale systems and online services. The company confirmed that the attackers had demanded a ransom but said it refused to negotiate.

“The company maintains a principled position of rejecting any interaction with cybercriminals and refuses to fulfill their demands,” Novabev Group said in a statement on Wednesday. There is no indication so far that customer data has been compromised, though an investigation is ongoing, the company added.

The identity of the attackers remains unknown. No ransomware group has claimed responsibility for the incident, and Novabev has not publicly attributed the attack.

Novabev Group is a major Russian producer and distributor of spirits, including the Beluga and Belenkaya vodka brands.

The cyberattack has halted product shipments from Novabev for at least two days, according to local retailers quoted by Russian media outlet Vedomosti. Customers also reported being unable to pick up orders from retail locations or parcel lockers, with customer service offering to extend storage periods for online purchases.

WineLab’s stores are currently closed in major cities, including Moscow, St. Petersburg and surrounding regions, according to location data from Yandex Maps. Novabev’s website and mobile app also remain offline.

Forbes Russia estimated that each day of downtime could cost WineLab 200 million to 300 million rubles ($2.6 million to $3.8 million) in lost revenue. Cybersecurity experts interviewed by Forbes said they could not recall a comparable case in which a major Russian retail chain was forced to shut down entirely due to a cyberattack.

Novabev said its internal IT team is working “around the clock” with external specialists to restore operations and strengthen defenses against future threats.