Email addresses were among the personal data points stolen by hackers in a breach of T-Mobile.
The company announced on Thursday that it had suffered the breach, potentially affecting millions of customers, and had reported it to authorities.
“Out of an abundance of caution, we wanted to let you know about an incident that we recently handled that may have impacted some of your personal information,” it says on its website.
The firm adds that the unauthorized access to data was discovered on Monday, August 20.
Motherboard, which first reported the episode, said that the breach affected 2 million customers.
It was not clear at deadline if the breach had caused any harm.
“None of your financial data (including credit card information) or social security numbers were involved, and no passwords were compromised,” the company said on its website,” the firm says.
It adds, “however, you should know that some of your personal information may have been exposed, which may have included one or more of the following: name, billing zip code, phone number, email address, account number and account type (prepaid or postpaid).”
Customers are encouraged to contact the company with questions.
“We take the security of your information very seriously and have a number of safeguards in place to protect your personal information from unauthorized access. We truly regret that this incident occurred and are so sorry for any inconvenience this has caused you.”