The shutdown has raised fears of a price spike at gasoline pumps.
Colonial transports 2.5 million barrels per day of gasoline, diesel, jet fuel and other refined products.
Colonial said it shut down systems to contain the threat after learning of the attack on Friday.
NEW YORK (Reuters) -Top US fuel pipeline operator Colonial Pipeline has shut its entire network, the source of nearly half of the U.S. East Coast`s fuel supply, after a cyber attack that the company said was caused by ransomware.
The incident is one of the most disruptive digital ransom operations ever reported and has drawn attention to how critical U.S. energy infrastructure is vulnerable to hackers. The shutdown has raised fears of a price spike at gasoline pumps ahead of peak summer driving season if it persists.