Colonial Pipeline announced late on Wednesday that it had restarted operations of the largest fuel pipeline network in the US, which had been shut down after a ransomware attack, leading to fuel shortages across the eastern US for almost a week.
The ransomware attack last week halted 2.5 million barrels per day of fuel shipments. The pipeline stretches 5,500 miles (8,850 kilometres) from US Gulf Coast oil refineries to consumers in mid-Atlantic and south-east states.
The company warned that service would still be rocky in the days to come as the pipeline came back online.
"Following this restart, it will take several days for the product delivery supply chain to return to normal," a company statement read. "Colonial will move as much gasoline, diesel and jet fuel as is safely possible and will continue to do so until markets return to normal."
Colonial, which each day normally ships about 2.5 million barrels, warned the line may go down again from time to time while it’s in the process of restarting.
In a separate bulletin to its shippers, it said the company was physically starting operations even before its business systems –which process nominations for space on the pipeline and schedule them – are back up and running. As a result, it’ll be using schedules that were set five days ago until its systems are back in service, the notice shows.
As the shutdown of the pipeline network entered its the sixth day, Washington officials pledged to help alleviate supply issues.
Shortly before the Colonial announcement, President Joe Biden said he was expecting good news on the situation and touted the steps he had taken to relieve supply disruptions.
“I’ve lifted some of the restrictions on the transportation of fuel as well as access to the United States military providing fuel, and with vehicles to get it there, places where it’s badly needed,” Mr Biden told reporters at the White House.
The White House said top officials were considering new ways to alleviate the shortages, following several waivers easing quality standards for petrol and extending working hours for fuel lorry drivers to boost shipments.
Congressional committee members have asked for a formal briefing from a White House inter-agency task force about the federal response to the most disruptive cyberattack on US energy infrastructure.
Privately owned Colonial Pipeline opened portions of the line manually in Georgia, Maryland, New Jersey and North and South Carolina. It also accepted two million barrels of fuel to begin a restart that would "substantially" restore operations by week's end, the company said.
The supply crunch sparked panic buying in the US south-east, bringing long lines and high prices at fuel stations before the Memorial Day holiday weekend at the end of May, the traditional start of the peak summer driving season.
The average national petrol price rose to above $3.00 a gallon on Wednesday, the highest since October 2014, the American Automobile Association said.
Nearly 60 per cent of fuel stations in metro Atlanta were without gasoline on Wednesday, tracking firm GasBuddy said.
More than 70 per cent of stations were out in metro Charlotte and Raleigh, North Carolina, and Pensacola, Florida. Virginia and South Carolina also saw relatively high outages.
The US Consumer Product Safety Commission posted a Twitter thread issuing guidance to Americans shopping for gas, starting with, "Do not fill plastic bags with gasoline."
Stevenson Rosslow, 47, was filling up his Lexus with regular gas at a BP station in south Atlanta on Wednesday morning.
"This takes premium, but they're out," said Mr Rosslow, the owner of the Wrecking Bar Brewpub in Atlanta's Reynoldstown neighbourhood. "Even at that, the price jumped to what, $3.39?"
The station Mr Rosslow stopped at was the fourth he had tried. "I think we're having a problem here because of hoarding," he said.
Four south-eastern states — Florida, North Carolina, Virginia and Georgia — joined federal regulators in relaxing driver and fuel restrictions to speed deliveries of supplies. Georgia suspended sales tax on petrol until Saturday.
The Federal Bureau of Investigation has accused a shadowy criminal gang called DarkSide of the ransomware attack. DarkSide is believed to be based in Russia or Eastern Europe.
Russia's embassy in the US rejected speculation that Moscow was behind the attack. Mr Biden on Monday said there was no evidence so far that Russia was responsible.
It is unknown how much money the hackers are seeking and Colonial has not commented on whether it would pay. However, Bloomberg reported on Thursday that a ransom of almost $5m had been paid.
Gulf Coast refiners that move fuel to market on the Colonial Pipeline have cut processing. Total trimmed petrol production at its Port Arthur, Texas, refinery, and Citgo Petroleum pared back at its Lake Charles, Louisiana, plant.
Citgo said it was moving products from Lake Charles and "exploring alternate supply methods into other affected markets". Marathon Petroleum said it was "making adjustments".
Colonial also serves US airports including Atlanta's Hartsfield-Jackson Airport, the world's busiest by passenger traffic.
Several airlines have been transporting fuel by lorry or fuelling planes at destinations rather than at East Coast origins. American Airlines has made changes to two long-haul flights out of Charlotte, North Carolina – one of its hub airports – through to Friday.