The North Korean military on Monday warned of “physical measures” to turn future South Korean sites for Terminal High-Altitude Area Defense (THAAD), the U.S. made missile defense system, into a “sea of fire” and a “pile of ash.”

The North Korean announcement, which was reported through its state-owned Rodong Sinmun and Korean Central News Agency (KCNA), was released three days after Washington and Seoul made the decision for THAAD to be deployed in South Korea, though a specific location has yet to be decided.