A unique Colorado Air National Guard unit is keeping its eye on the skies for North Korean missiles after Kim Jong-un reportedly ordered its short- and long-range missile batteries to standby for attacks on U.S. bases in South Korea and the Pacific.

Sky News reports that the young North Korean leader met with his top generals late Wednesday night and signed the order in response to a show of force by the United States, which sent two nuclear-capable B-2 bombers to participate in a military exercise with South Korea in recent days.

Jong-un earlier had nullified the 1953 armistice and threatened to nuke the United States and begin an “all out war.”