The government says North Korea is operating a cyber warfare unit that collects intelligence information from South Korea and the United States to establish combat simulations.

Government authorities said the North has been running a so-called “technology reconnaissance team” that hacks into South Korean and U.S. military computer networks to collect classified information and disrupts their systems with computer viruses.

The unit is said to be composed of roughly 100 hackers from a leading computer science institution in Pyongyang.