A security breach has affected about 714 people who used a vendor's web server to pay bills online to Tehachapi Valley Healthcare District and Adventist Health, according to a Friday news release from Adventist Health Tehachapi Valley.

The vendor, Fast Health, realized that an "unauthorized, third-party altered code on their server" was being used to capture credit card information for patients, the news release said. This may have included billing addresses, phone numbers, credit card numbers and codes and names.

Information about medical records for patients was not breached, however.

The news release also said the breach "only potentially affected Fast Health's online bill-pay platform from Jan. 14, 2016 to Dec. 20, 2016."

Fast Health made known the breach to Adventist Health on May 9 and has removed the code from the servers.

Fast Health will send letters to anyone who might be impacted. Patients or family who paid their bills during that time can call Fast Health for more information at 1-844-534-0814.

Payers should review their financial statements for any suspicious activity.

"We will continue to review this important security issue with Fast Health and provide additional follow-up information as it becomes available," said Teresa Adamo, marketing manager for Adventist Health.