The U.S. Treasury Department on Friday imposed sanctions on alleged hacker Yin Kecheng and cybersecurity company Sichuan Juxinhe Network Technology Co., accusing both of being involved in a series of hacks against American telecom companies.

The Treasury Department’s Office of Foreign Assets Control (OFAC) announced on Friday that it had sanctioned a China-based cybersecurity company, known as Sichuan Juxinhe Network Technology, which it says is directly linked to the China-backed Salt Typhoon hacking group.