T-Mobile has severed its connection to the unnamed wireline provider, which it suspects may still be compromised.

T-Mobile says the Chinese "Salt Typhoon" hackers who recently compromised its systems as part of a series of telecom breaches first hacked into some of its routers to explore ways to navigate laterally through the network.

T-Mobile, one of America's largest wireless carriers, has confirmed it was compromised in a recent wave of sophisticated cyberattacks targeting U.S. telecom companies.

Suspicious behavior on T-Mobile US Inc.’s network devices tipped off the company to a breach that was potentially part of a sprawling cyber-espionage campaign that has raised urgent questions about the exposure of a critical sector of the economy.

The mobile carrier provided its first detailed rundown of how it stopped hackers from infiltrating its networks.