Service providers and other systems have been reported to have gotten infiltrated over the recent days. Twenty-two million government employees from the United States have been hacked a few months back, in June. And at around the same time, Italian group The Hacking Team, which specializes in providing surveillance and hacking services, has also been infiltrated. Data stolen from the group have been posted in public domains, revealing secret transactions of the elusive Hacking Team.

Now, mobile carrier T-Mobile has also been reported to have data stolen. Credit checking organization Experian puts the number of stolen customer data at 15 million, which is massive. According to Telegraph UK, hackers have been able to access the data of customers who applied for T-Mobile services between Sept. 1, 2013 and Sept. 16, 2015. The data stolen have been found on sale on the Dark Web, according to security startup Trustev.

The "FULLZ" data, slang for full package of personal information which includes social security number, birthdate and account numbers, among other things, have been discovered to be in the Dark Web on Oct. 1, Thursday . "This morning they saw listings go up for "FULLZ" data that matches the same types of information that just came out of the Experian hack," a Trustev spokesperson told Venturebeat. 

For its part, Experian has immediately notified authorities of the hacking incident and said, "there is no evidence to date that the data has been used inappropriately." T-Mobile CEO John Legere is unhappy with the resolution following the incident. T-Mobile customers can now sign up for free credit monitoring services owned by Experian, which lasts for two years. Customers may sign up at www.protectmyID.com/securityincident.

Park Record reports that Legere took to Twitter to air his sentiments, saying, "I hear you re: Experian as service protection option. I am moving as fast as possible to get an alternate option in place by tomorrow." Legere earlier said that he is "incredibly angry" about the incident and is re-evaluating T-Mobile's relationship with Experian.