The entrance of Colonial Pipeline Company is shown Wednesday, May 12, 2021, in Charlotte, N.C. Several gas stations in the Southeast reported running out of fuel, primarily because of what analysts say is unwarranted panic-buying among drivers, as the shutdown of a major pipeline by hackers entered its fifth day.

CLEMMONS, N.C. — Motorists found gas pumps shrouded in plastic bags at tapped-out service stations across more than a dozen U.S. states Thursday while the operator of the nation's largest gasoline pipeline reported making “substantial progress” in resolving the computer hack-induced shutdown responsible for the empty tanks.

About 70% of North Carolina's gas stations were still without fuel amid panic-buying and about half the stations in Virginia, South Carolina and Georgia were tapped out, GasBuddy.com reported. Washington, D.C., was among the hardest-hit locations, with 73% of stations out, the site's tracking service showed.

President Joe Biden said Thursday that U.S. officials do not believe the Russian government was involved in the hack of the Colonial Pipeline, which stretches from Texas to New Jersey. But he added, “We do have strong reason to believe that the criminals who did the attack are living in Russia. That's where it came from.”

A cyberattack by hackers who lock up computer systems and demand a ransom to release them hit the pipeline on Friday. The hackers did not take control of the pipeline's operations, but Colonial shut it down to contain the damage.

The U.S. was in direct communication with Moscow about the need to take action against ransom networks, Biden said. The FBI has said the ransomware belonged to a criminal syndicate known as DarkSide.

After restarting operations Wednesday, Georgia-based Colonial Pipeline said in a Thursday update that gasoline deliveries were underway in all of its markets.