A majority of Iran's gas stations went out of service on Monday following cyberattacks by a hacking group that Tehran accuses of having links to Israel.
Iran's Oil Minister Javad Owji confirmed that the nationwide disruption to petrol stations was caused by a cyberattack.
Owji had earlier told Iranian state TV that services had been disrupted at about 70% of Iran's petrol stations and that outside interference was a possible cause. He later said 1,650 petrol stations were operational. The ministry supervises 3,800 petrol stations.
A hacker group dubbed "Gonjeshke Darande," or predatory sparrow, claimed it was behind the disruption, Iranian state TV and Israeli local media reported.
"This cyberattack was carried out in a controlled manner to avoid potential damage to emergency services," the group said in its statement, according to Iranian media.
Iran's civil defense agency, which is responsible for the country's cybersecurity, said it was still considering all possible causes for the disruptions as it investigated.
Iranian state media added that the hacker group had in the past claimed cyberattacks against Iranian petrol stations, rail networks and steel factories.
A major cyberattack in Iran in 2021 also disrupted the sale of fuel, causing long queues at stations across the country where pump prices are heavily subsidized. Iran had said Israel and the United States were the likely culprits behind those attacks.
Monday's disruption began early and was especially acute in Tehran, forcing many petrol stations to operate manually, Iranian media reported.
"At least 30% of gas stations are working, with the rest gradually resolving the disruption in services," Owji said earlier Monday. The country has some 33,000 gas stations.
Reza Navar, a spokesperson for Iran's petrol stations association told the semi-official Fars news agency that there was no fuel supply shortage but called on drivers to not go to petrol stations.
"A software problem with the fuel system has been confirmed in some stations across the country and experts are currently fixing the issue," Navar said.
Earlier, the Oil Ministry told state TV that the disruption was not linked to plans to increase the price of fuel, a policy that caused widespread protests in 2019 and led to violent repression.
State TV said petrol stations were seeking to provide fuel manually and that it would take at least six to seven hours to resolve the problems.
Israel has not yet commented on the cyberattack in Iran.
Israel's Cyber Unit on Monday said Iran and Hezbollah were behind an attempted cyberattack on a hospital in northern Israel about three weeks ago. It said that the attack was thwarted but that the hackers could retrieve "some of the sensitive information stored in the hospital's information systems."
Iran disconnected much of its government infrastructure from the internet after the Stuxnet computer virus – widely believed to be a joint U.S.-Israeli creation – disrupted thousands of Iranian centrifuges in the country's nuclear sites in the late 2000s.
Long sanctioned by the West, Iran faces difficulties getting up-to-date hardware and software, often relying on Chinese-manufactured electronics or older systems no longer being patched by manufacturers. That would make it easier for a potential hacker to target. Pirated versions of Windows and other software are common across Iran.