North Korea is blasting South Korea for allowing civilians and reporters to visit the Demilitarized Zone (DMZ) as part of projects to mark the 60th anniversary of the start of the Korean War.

In a statement issued Monday, a North Korean official at the truce village of Panmunjeom threatened to retaliate, calling the South Korean government’s decision to allow visits “a hostile act.”

The North warned that an unpredictable situation, including a loss of lives, could occur if South Korea and the U.S. continue to “misuse” the Demilitarized Zone for inter-Korean confrontation.

The Defense Ministry in Seoul and the South Korean Army signed in February a memorandum of understanding with 15 media companies that will allow journalists to visit the DMZ later in the year.