BOSTON (AP) — Attorney General Martha Coakley says 73,000 Massachusetts consumers may have been affected by a data breach at TD Bank.

Coakley said Friday the bank has informed her office that it lost unencrypted backup data tapes with personal information including account information and Social Security numbers. She said the bank has begun notifying 267,000 customers nationwide, including those in Massachusetts.

The bank says it isn't aware that any of the customer information has been misused since the tapes were lost in March, but can't rule it out.

Coakley said affected consumers should take advantage of credit monitoring offered by the bank, avoid giving out sensitive information in response to unsolicited emails, calls or mailings, and carefully review their credit card and financial accounts.