Colonial Pipeline hackers stole data on Thursday

The hackers who caused Colonial Pipeline to shut down on Friday began their cyberattack against the top U.S. fuel pipeline operator a day earlier and stole a large amount of data, Bloomberg News reported citing people familiar with the matter.

The attackers are part of a cybercrime group called DarkSide and took nearly 100 gigabytes of data out of Colonial’s network in just two hours on Thursday, Bloomberg reported late Saturday, citing two people involved in the company’s investigation.

Colonial did not immediately reply to an email from Reuters seeking comment outside usual U.S. business hours.

Colonial Pipeline shut its entire network, the source of nearly half of the U.S. East Coast’s fuel supply, after a cyber attack that involved ransomware.

(Reporting by Aakriti Bhalla in Bengaluru; Editing by Himani Sarkar)