Internet company Yahoo said Tuesday that all of its 3 billion user accounts were affected in a 2013 data breach -- three times as many as it first reported late last year.
Yahoo, which was purchased by telecommunications giant Verizon in June and is now part of Verizon subsidiary Oath, said in a statement that all Yahoo user accounts were affected in the August 2013 data theft.
In December 2016, Yahoo said more than one billion of its user accounts were affected.
"Subsequent to Yahoo's acquisition by Verizon, and during integration, the company recently obtained new intelligence and now believes, following an investigation with the assistance of outside forensic experts, that all Yahoo user accounts were affected by the August 2013 theft," the statement said.
"Yahoo is sending email notifications to the additional affected user accounts. The investigation indicates that the user account information that was stolen did not include passwords in clear text, payment card data, or bank account information," it added.
The company said it is continuing to work closely with law enforcement.
Yahoo sold most of its business to Verizon in June for $4.48 billion, except its stakes in Alibaba Group and Yahoo Japan, and has since taken the name Altaba.
By Ovunc Kutlu in New York