(NewsNation) — Many victims of Chinese hacking efforts have not yet been notified by their phone carriers, NBC News is reporting.

Carriers including AT&T and Verizon have warned some customers that their calls may have been listened to and their texts read, but they have not informed hacking victims that they were specifically targeted.

Officials with the FBI and Cybersecurity and Infrastructure Security Agency have urged Americans to use encrypted messaging apps to ensure their communications stay hidden from the alleged Chinese cyberattack.

The hacking campaign accessed the metadata of more than a million people, NBC News reported, citing an industry source briefed on the matter. And there is no indication that those impacted will be notified in the near future.

Hackers targeted data from phones used by both the Donald Trump and Kamala Harris campaigns, according to reports in October.

NewsNation also confirmed, per a Democratic source briefed, that the Chinese Communist Party hack targeted prominent Democrats, including Senate Majority Leader Chuck Schumer’s staff.

Alan Butler, the executive director and president of the nonprofit Electronic Privacy Information Center, emphasized to NBC that “having one’s phone metadata exposed is a clear violation of privacy.”

“You should be upset, because carriers’ deficient practices resulting in the exposure of whether you called an oncologist or your church is enough of a violation, regardless of whether the actual content of those calls was also disclosed,” Butler told NBC News.