TD Bank (NYSE: TD) is notifying more than 267,000 of its U.S. customers of the loss of two unencrypted backup tapes containing personal data such as Social Security numbers, according to a press release from the office of the Massachusetts Attorney General, who said more than 73,000 of the potentially affected customers are in Massachusetts.

The server backup tapes went missing in March. The Massachusetts AG's alert from Friday said TD Bank was unaware of any misuse of personal information, but could not rule out the possibility. Information on the tapes may include bank account numbers, dates of birth, Social Security numbers, and driver's license numbers.

Based in Canada, TD Bank serves more than 7.4 million customers through nearly 1,300 retail locations in the U.S. in the Northeast, the mid-Atlantic, metro D.C., the Carolinas, and Florida.

The Attorney General's Office suggested customers avail themselves of credit monitoring services being offered by the bank.

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