And there's this:
Next-Level Spying: How China Read The West's Wiretaps For Years
https://www.zerohedge.com/geopolitical/next-level-spying-how-china-read-wests-wiretaps-years
For approximately four years, operators linked to the MSS’s Chengdu bureau had the capability to see not just who British officials were calling, but whom the FBI was investigating, which Chinese operatives were under surveillance, what the United States knew about Beijing’s activities, and when counterintelligence was getting close. They could geolocate millions of individuals. They could record phone calls at will.They compromised the surveillance of their own surveillers, achieving the counterintelligence equivalent of reading the other side’s playbook while the game was in progress.