In 2018, a hacker hired by the Mexican Sinaloa drug cartel run by the infamous kingpin Joaquín “El Chapo” Guzmán spied on the U.S. Embassy in Mexico City with the goal of identifying “people of interest” for the cartel to target and kill, according to a new U.S. government watchdog report.

A hacker hired by a notorious Mexican drug cartel reportedly accessed an FBI official’s phone records and surveillance cameras to help find and kill FBI informants.

The hacker was able to break into the agent’s phone remotely and watch their incoming and outgoing calls, and even monitor the phone’s geolocation.