ROCHESTER, N.Y. (AP) -- New York State Electric & Gas and Rochester Gas and Electric said Monday that a subcontractor's employee got unauthorized access to customer information.
The records include Social Security numbers, dates of birth and, for some customers, bank account numbers.
The companies said that they have begun notifying customers of the breach.
An employee at a software consulting firm hired by the companies allowed unauthorized access to customer-information systems, they said.
The companies said there was no evidence that the data has been misused. They said they reported the incident to law enforcement, hired computer-forensics experts, and offered customers a year of free credit-monitoring service from Experian.
Both companies are owned by Spanish utility company Iberdrola S.A.
A toll-free help line for customers was set up at 1-877-736-4495 and, for international callers, 1-479-573-7373. It will be staffed from 9 a.m. to 9 p.m. EST on Monday through Friday and 11 a.m. to 8 p.m. on Saturday and Sunday, the companies said.
NYSEG has 878,000 electricity customers and 261,000 natural gas customers in upstate New York, and Rochester Gas and Electric has 367,000 electricity customers and 303,000 natural gas customers in nine counties around Rochester.