MIAMI (CBSMiami) – A security alert for people in Pompano Beach.

The city says a third-party software vendor used for online water bill payments has been compromised.

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The city says unauthorized access was gained to credit or debit card data used for payments made through the city’s website between August 27th and October 14th.

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An investigation was launched as soon as the breach was discovered.

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Letters have been mailed to all water customers possibly affected by the breach.