T-Mobile US was reportedly among the operators hit by a China-linked cyberattack exposed by two government agencies last week, although the company played down the impact of the breach.

Bloomberg reported the US operator revealed in a statement it was closely monitoring the industry wide-attack, but added it had not seen a significant impact to T-Mobile systems or data, and had no evidence of impact or exfiltration of any customer information.

“We will continue to monitor this closely, working with industry peers and the relevant authorities,” the company added.

Last week, the FBI and Cybersecurity and Infrastructure Security Agency (CISA) stated it had uncovered a “broad and significant” cyber espionage campaign targeting commercial telecoms infrastructure in the country, which was blamed on China-affiliated actors.

While the companies impacted by the breach were not named, news outlets reported last month networks run by AT&T, Verizon and Lumen had been attacked by Salt Typhoon, a China-linked group.

Hackers attempted to steal customer call record data and compromised private communications for a limited number of people involved in government or political activity.

In response to the FBI and CISA’s statement, China foreign ministry spokesman Lin Jian told Bloomberg the country “has no interest in interfering in other countries intel affairs through cyberspace”.