Following reports that an unauthorized party was able to gain access to an Experian server that contained the personal information of more than 15 million T-Mobile users, including 12,068 Maine residents, Attorney General Janet T. Mills Oct. 6 offered consumers tips to guard against potential identity theft.

“The Maine Attorney General’s Office takes this breach very seriously and we are encouraging any T-Mobile customer to take pro-active steps to protect themselves from potential ID theft,” Mills said. “We anticipate working with attorneys general across the country on this matter and have been in touch with representatives of Experian and T-Mobile. Experian is offering affected customers free credit monitoring for two years; I strongly advise any affected T-Mobile customers to take them up on this offer.”

According to T-Mobile and the credit reporting company Experian, the breach compromised data that was used by T-Mobile in connection with credit checks of individuals who applied for T-Mobile services from Sept. 1, 2013, through Sept. 16, 2015. The data included name, address, birth date, Social Security numbers, other ID numbers (such as driver’s license, military ID, or passport numbers), and additional information used in T-Mobile’s credit assessment.

The Maine Attorney General’s Office offers consumers the following tips to guard against identity theft:

Monitor your credit report. You are entitled to one free credit report every 12 months from each of the three nationwide credit bureaus (you can request one free report from a different bureau every four months to monitor throughout the year).

Request a “fraud alert” be placed on your accounts to alert you to any attempts to open a line of credit in your name by calling one of the national credit bureaus before they are approved. When you call, an initial fraud alert (90 days) will be placed on your credit report and a free copy of your credit report will be sent to you.

Consider placing a “security freeze” on your credit report to prohibit the release of any information from your report without your written authorization. (A freeze is currently subject to a fee; however, a new law eliminates that fee after Oct. 15).

Beware of phishing attempts and unsolicited calls or emails offering credit monitoring or identity theft services. Consumers should never provide their social security number, credit card or other personal information in response to unsolicited emails or calls.

If you find unexplained activity on your credit reports or if you believe you are the victim of identity theft, there are important steps to take to protect yourself. Contact the Attorney General's Consumer Protection Division at 800-436-2131, review the Attorney General’s Identity Theft webpage, contact regulators at the Maine Bureau of Consumer Credit Protection at 800-332-8529, or view the Federal Trade Commission's identity theft resource, available at identitytheft.gov .