Madison Square Garden disclosed Tuesday it was hit with a massive credit card breach at five of its venues that lasted nearly a year.

MSG said during the last week in October it found unauthorized external access into the payment system and a program that looks for credit card data as a payment is being processed.

Food and beverage items at Madison Square Garden, the Theater at Madison Square Garden, Radio City Music Hall, Beacon Theater and Chicago Theater between November 9, 2015 and October 24 might have been affected, the venue wrote on its website.

Data contained in the magnetic stripe on the back of payment cards swiped in person to purchase merchandise and food and beverage items at Madison Square Garden, the Theater at Madison Square Garden, Radio City Music Hall, Beacon Theater, and Chicago Theater between November 9, 2015 and October 24, 2016 may have been affected, including credit card numbers, cardholder names, expiration dates and internal verification codes. Not all cards used during this time frame were affected. This incident did not involve cards used on MSG websites, at the venues’ Box Offices, or on Ticketmaster.

MSG has stopped the breach and is cooperating with authorities, it said.

“It is always advisable to remain vigilant to the possibility of fraud by reviewing your payment card statements for any unauthorized activity,” the venue advised. “You should immediately report any unauthorized charges to your card issuer because payment card rules generally provide that cardholders are not responsible for unauthorized charges reported in a timely manner.”

MSG said anyone with questions with regard to the breach can call them at 844-319-9619 from 9 a.m. to 9 p.m. EST, Monday to Friday (excluding major holidays).

To further protect yourself, the venue also suggested ordering your free annual credit report.