U.S. telecom giants AT&T and Verizon say they have secured their networks after being targeted by the China-linked Salt Typhoon cyberespionage group.

In a statement given to Read on Monday, AT&T spokesperson Alexander Byers said the company detects “no activity by nation-state actors in our networks at this time.”

Verizon spokesperson Richard Young said in an emailed statement to Read on Sunday that the organization has “contained the cyber incident brought on by this nation-state threat actor,” and that it has not detected any threat actor activity on its network “for some time.”

Verizon’s containment of the incident has been confirmed by a “highly respected cybersecurity firm,” the company said, but Young declined to name the third-party organization.

While the scale of these Salt Typhoon breaches is not yet known, AT&T said China-backed hackers targeted “a small number of individuals of foreign intelligence interest”, adding that it was aware of “relatively few instances” in which an individual’s information was compromised.

Verizon said that the hackers specifically targeted a “small number of high-profile customers in government.”

“Immediately upon learning of this incident, Verizon took several key actions to protect its customers and its network, including partnering with federal law enforcement and national security agencies, industry partners, and private cybersecurity firms,” Vandana Venkatesh, Verizon’s chief general officer, said in a statement. “After considerable work addressing this incident, we can report that Verizon has contained the activities associated with this particular incident.”

This marks AT&T and Verizon and first acknowledgment of their being impacted by the Salt Typhoon campaign. News first broke in October that the hackers had compromised the networks of some of the largest U.S. phone and internet companies to gather intelligence on U.S. citizens.

U.S. officials said earlier this month that at least eight telecommunications providers had been targeted, including Lumen (formerly CenturyLink) and T-Mobile. On Friday, Anne Neuberger, deputy national security adviser for cyber and emerging technology, said a ninth victim had been identified, according to Reuters.

Neuberger, who didn’t name the newly identified victim, said one of the nine telecoms breached involved an administrator account that had access to over 100,000 routers.

Updated with post-publish comment from AT&T.