T-Mobile on Friday released more details about a hack into its systems, noting that more customers were affected than it previously disclosed. Further, the company said hackers obtained some customers’ IMEI and IMSI phone data alongside other personal information, potentially paving the way for deeper security breaches. The Wall Street Journal reported that the FBI is aware of the situation and that the FCC has opened an investigation into the matter. News of the hack broke early this week, and T-Mobile has been issuing updates of its investigation into the issue since then. The company’s latest update indicates hackers obtained more data on its customers than T-Mobile initially disclosed. “We have now also determined that phone numbers, as well as IMEI and IMSI information, the typical identifier numbers associated with a mobile phone, were also compromised. Additionally, we have since identified another 5.3 million current postpaid customer accounts that had one or more associated customer names, addresses, date of births, phone numbers, IMEIs and IMSIs illegally accessed,” the company said in a statement.