The New York Yankees issued an apology to season tickets holders this week for accidently releasing the personal information of thousands of individual fans.

The breach was an internal one, according to the team, after an employee mistakenly sent out an email on Monday, April 25, that contained a spreadsheet attachment with the personal information of about 17,000 season ticket holders. The email was sent to hundreds of other season ticket holders, but the information has since been distributed around the internet.

In a statement released to all season ticket holders last night, April 27, Yankees officials stressed that the information in the spreadsheet contained only names, addresses, phone and/or fax numbers, email addresses, seat and Yankees account numbers, and other information related to the season tickets. The 17,000 names represent about half of all Yankees season ticket holders.

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No Social Security or credit card numbers, birthdays, passwords or other critical data, were exposed, the team said.

“The Yankees deeply regret this incident, and any inconvenience that it might cause,” the team said in a statement.

Reportedly, once the employee realized the mistake, they tried to retrieve the email but it was too late. The team has since taken undisclosed steps to ensure such a breach does not happen again.

The incident comes at a time when the public is particularly attuned to issues of online security after multiple news stories have chronicled various breaches, and consumer electronics giant Apple was forced to apologize for reportedly tracking the whereabouts of iPhone users.

Last year, international soccer organization FIFA was embroiled in an information breach saga after it was discovered that tens of thousands of names and passport numbers of World Cup ticket buyers were exposed.

“I don’t feel comfortable with people having my account number out there attached to my name,” Yankees season ticket holder Nick Chopey told the New York Daily News. “They could maybe figure out my password and that could cause me problems with my tickets…. This certainly doesn’t make you feel very well.”

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Below is the Yankees’ statement released to season ticket holders:

Dear Yankees Season Ticket Licensee,

We are writing to inform you about an accidental electronic distribution of information that you have previously supplied to the New York Yankees.

Monday evening, April 25, 2011, an employee of the Yankees sent an e-mail to several hundred Yankees Season Ticket Licensees. The e-mail mistakenly attached an internal Yankees spreadsheet that listed the following information associated with your New York Yankees account:

– Your name, and the address, phone number(s), fax number, and e-mail address that you previously provided to the Yankees.

– Your seat numbers, Yankees account number, Yankees account representative name, and the ticket package code associated with your account.

NO OTHER INFORMATION WAS INCLUDED IN THE DOCUMENT THAT WAS ACCIDENTALLY ATTATCHED TO THE APRIL 25TH E-MAIL. THE DOCUMENT DID NOT INCLUDE ANY BIRTH DATES, SOCIAL SECURITY NUMBERS, CREDIT CARD DATA, BANKING DATA OR ANY OTHER PERSONAL OR FINANCIAL INFORMATION.

Please note, immediately upon learning of the accidental attachment of the internal spreadsheet, remedial measures were undertaken so as to assure that a similar incident could not happen again.

The Yankees deeply regret this incident, and any inconvenience that it might cause.