Hackers tied to the Chinese government have compromised the law enforcement wiretap network of U.S. telecom companies, and security analysts aren't sure how bad it is yet.

A group of hackers known as Salt Typhoon gained access to U.S. wiretap systems and likely have had access for several months or longer. The systems, mandated under a 30-year-old federal law, were part of the Communications Assistance for Law Enforcement Act, or CALEA, which became law in 1994, Apple Insider reports.

These systems would have given the group access to a wealth of information on U.S. businesses and citizens alike. Verizon Communications, AT&T, and Lumen Technologies are among the companies whose networks were breached by the recently discovered intrusion, sources toldThe Wall Stereet Journal.

The goal of the attack seemed to be geared toward intelligence collection and constitutes a major national security risk. The attack is still being investigated as security analysts work to confirm what data — and how much — hackers managed to make off with.